[StainlessS]

So this is relevant at end of log (video pass only)

-[Error] Log for job2 (video, HxH 008.avs -> )
--[Information] [24/4/2019 6:04:22 PM] Started handling job
--[Information] [24/4/2019 6:04:22 PM] Preprocessing
--[Information] [24/4/2019 6:04:22 PM] AviSynth input script

---[NoImage] LoadPlugin("D:\SRK\MeGUI-2836-32\MeGUI-2836-32\tools\avs\plugins\directshowsource.dll")
---[NoImage] DirectShowSource("D:\New folder\HxH 008.mkv", fps=23.976, audio=false, convertfps=true).AssumeFPS(24000,1001)
---[NoImage] ConvertBits(8)
---[NoImage] #deinterlace
---[NoImage] #crop
---[NoImage] LanczosResize(1256,704) # Lanczos (Sharp)
---[NoImage] #denoise
---[NoImage] LoadPlugin("D:\SRK\MeGUI-2836-32\MeGUI-2836-32\tools\avisynth_plugin\VSFilter.dll")
---[NoImage] TextSub("D:\New folder\AnimeKaizoku_HxH_E008_x265_BD_720p.ass", 1)

--[Information] [24/4/2019 6:04:23 PM] resolution: 1256x704
--[Information] [24/4/2019 6:04:23 PM] frame rate: 24000/1001
--[Information] [24/4/2019 6:04:23 PM] frames: 33931
--[Information] [24/4/2019 6:04:23 PM] length: 00:23:35.205
--[Information] [24/4/2019 6:04:23 PM] aspect ratio (avs): 157:88 (1.784)
--[Information] [24/4/2019 6:04:23 PM] color space: RGB32
--[Error] [24/4/2019 6:04:23 PM] color space not supported
--[Information] [24/4/2019 6:04:23 PM] Job command line: "cmd.exe" /c ""D:\SRK\MeGUI-2836-32\MeGUI-2836-32\tools\ffmpeg\ffmpeg.exe" -loglevel level+error 
        -i "D:\New folder\HxH 008.avs" -strict -1 -f yuv4mpegpipe - | "D:\SRK\MeGUI-2836-32\MeGUI-2836-32\tools\x264\x264.exe" --pass 1 --bitrate 390 
        --stats "D:\New folder\HxH 008.stats" --keyint 240 --ref 6 --partitions all --stitchable --sar 1:1 --frames 33931 --output NUL --stdin y4m -"
--[Information] [24/4/2019 6:04:24 PM] Process started
--[Information] [24/4/2019 6:04:24 PM] Standard output stream
--[Error] [24/4/2019 6:04:24 PM] Standard error stream
---[Error] [24/4/2019 6:04:25 PM] [yuv4mpegpipe @ 07d2fac0] [error] ERROR: yuv4mpeg can only handle yuv444p, yuv422p, yuv420p, yuv411p and gray8 pixel formats. And using 'strict -1' also 
        yuv444p9, yuv422p9, yuv420p9, yuv444p10, yuv422p10, yuv420p10, yuv444p12, yuv422p12, yuv420p12, yuv444p14, yuv422p14, yuv420p14, yuv444p16, yuv422p16, yuv420p16, gray9, gray10, 
        gray12 and gray16 pixel formats. Use -pix_fmt to select one.
---[Information] [24/4/2019 6:04:25 PM] [error] Could not write header for output file #0 (incorrect codec parameters ?): I/O error
---[Information] [24/4/2019 6:04:25 PM] [error] Error initializing output stream 0:0 -- 
---[Error] [24/4/2019 6:04:25 PM] y4m [error]: bad sequence header magic
---[Error] [24/4/2019 6:04:25 PM] x264 [error]: could not open input file `-'
--[Error] [24/4/2019 6:04:26 PM] Process exits with error: 0xFFFFFFFF (-1)
--[Information] [24/4/2019 6:04:26 PM] Job completed

Script

LoadPlugin("D:\SRK\MeGUI-2836-32\MeGUI-2836-32\tools\avs\plugins\directshowsource.dll")
DirectShowSource("D:\New folder\HxH 008.mkv", fps=23.976, audio=false, convertfps=true).AssumeFPS(24000,1001)
ConvertBits(8)
#deinterlace
#crop
LanczosResize(1256,704) # Lanczos (Sharp)
#denoise
LoadPlugin("D:\SRK\MeGUI-2836-32\MeGUI-2836-32\tools\avisynth_plugin\VSFilter.dll")
TextSub("D:\New folder\AnimeKaizoku_HxH_E008_x265_BD_720p.ass", 1)

Error

---[Error] [24/4/2019 6:04:25 PM] [yuv4mpegpipe @ 07d2fac0] [error] ERROR: yuv4mpeg can only handle yuv444p, yuv422p, yuv420p, yuv411p and gray8 pixel formats. And using 'strict -1' 
        also yuv444p9, yuv422p9, yuv420p9, yuv444p10, yuv422p10, yuv420p10, yuv444p12, yuv422p12, yuv420p12, yuv444p14, yuv422p14, yuv420p14, yuv444p16, yuv422p16, yuv420p16, gray9, gray10,
         gray12 and gray16 pixel formats. Use -pix_fmt to select one.

Either Add "ConvertToYV12" at end of script (I'm surprised if it does not ask to do this for you).

Or add DirectShowSource arg

DirectShowSource Docs

DirectShowSource (string filename, float "fps", bool "seek", bool "audio", bool "video", bool "convertfps", bool "seekzero", int "timeout", string "+pixel_type",int "framecount", string "logfile", int "logmask")

[EDIT: Looks like the '+' in above "+pixel_type" built-in v2.60std docs is wrong, should not be there. (is OK in WIKI docs)]

Script, added in blue

LoadPlugin("D:\SRK\MeGUI-2836-32\MeGUI-2836-32\tools\avs\plugins\directshowsource.dll")
DirectShowSource("D:\New folder\HxH 008.mkv", fps=23.976, audio=false, convertfps=true ,Pixel_Type="YV12" ).AssumeFPS(24000,1001)
ConvertBits(8)
#deinterlace
#crop
LanczosResize(1256,704) # Lanczos (Sharp)
#denoise
LoadPlugin("D:\SRK\MeGUI-2836-32\MeGUI-2836-32\tools\avisynth_plugin\VSFilter.dll")
TextSub("D:\New folder\AnimeKaizoku_HxH_E008_x265_BD_720p.ass", 1)

EDIT: Source seems to be 10 bit, dont know what this [Pixel_Type="YV12"] should be if not YV12, any suggestions for 10bit Planar ? (I never touch the stuff)
EDIT: Actually, the error tells what it can process, ie change above "YV12" to "yuv420p", (maybe directShowSource supports this also).

EDIT: Below from Wiki DirectShowSource docs, I dont know what would work if pixel_type="YV12" dont work,

string pixel_type = (auto)

Request a color format from the decompressor. Valid values are:

YV24, YV16, YV12, I420, NV12, YUY2, AYUV, Y41P, Y411, ARGB, RGB32, RGB24, YUV, YUVex, RGB, AUTO, FULL

By default, upstream DirectShow filters are free to bid all of their supported media types in the order of their choice. A few DirectShow filters get this wrong. The pixel_type argument limits the acceptable video stream subformats for the IPin negotiation. Note the graph builder may add a format converter to satisfy your request, so make sure the codec in use can actually decode to your chosen format. The MS format converter is just adequate. The "YUV" and "RGB" pseudo-types restrict the negotiation to all official supported YUV or RGB formats respectively. The "YUVex" also includes YV24, YV16, I420 and NV12 non-standard pixel types. The "AUTO" pseudo-type permits the negotiation to use all relevant official formats, YUV plus RGB. The "FULL" pseudo-type includes the non-standard pixel types in addition to those supported by "AUTO". The full order of preference is YV24, YV16, YV12, I420, NV12, YUY2, AYUV, Y41P, Y411, ARGB, RGB32, RGB24. Many DirectShow filters get this wrong, which is why it is not enabled by default. The option exists so you have enough control to encourage the maximum range of filters to serve your media. (See discussion.)

The non-standard pixel types use the following GUID's respectively :-

MEDIASUBTYPE_I420 = {'024I', 0x0000, 0x0010, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71};
MEDIASUBTYPE_YV24 = {'42VY', 0x0000, 0x0010, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71};
MEDIASUBTYPE_YV16 = {'61VY', 0x0000, 0x0010, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71};
MEDIASUBTYPE_NV12 = {'21VN', 0x0000, 0x0010, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71};

In other words, if pixel_type="AUTO", it will try to output YV24; if that isn't possible it tries YV16, and if that isn't possible it tries YV12, etc...
[EDIT: Actually looks like '+' is not wrong in docs]
For planar color formats, adding a '+' prefix, e.g. DirectShowSource(..., pixel_type="+YV12"), tells AviSynth the video rows are DWORD aligned in memory instead of packed. This can fix skew or tearing of the decoded video when the width of the picture is not divisible by 4.