[StainlessS]

See Avisynthesizer_Mod, a Windows Explorer SendTo type app.
Creates Avs files, Two modes of operation, concatenates selected files,
or (probably what you want)
Batch Mode, creates an Avs for each selected file [Can Group Select].

Uses Template [extension avst, in Avsynthesizer_Mod TEMPLATE directory] to create AVS files.
https://forum.doom9.org/showthread.p...ynthesizer_mod

EDIT: Simple Batch Mode template.

#ASYNTHER BATCH-AVISOURCE
# Above BATCH-AVISOURCE shown in GUI for template selection

# Below not enclosed in square brackets, so is Non-Repeating ie Batch Mode, multiple AVS files generated. 
FN = "___FILE___"

AVISource(FN)

Crop(32,0,-32,0) # Or whatever

# ... Etc

EDIT: Maybe something like this [Based on your C source code]

Batch_ISmile.avst

#ASYNTHER BATCH-ISMILE
# Above BATCH-ISMILE shown in GUI for template selection

FN = "___FILE___"

video = LSMASHVideoSource(FN).Crop(0, 0, 0, 0).ConvertToYV12(interlaced = false)
audio = LSMASHAudioSource(FN)
AudioDubStep = AudioDub(video, audio)
top_left     = LSFmod(AudioDubStep, strength = 200).crop(0, 0, -960, -540).Spline64Resize(900, 800).AddBorders(380,0,0,0) # top left
top_right    = LSFmod(AudioDubStep, strength = 200).crop(960, 0, 0, -540).Spline64Resize(900, 800).AddBorders(0,0,380,0)  # top right
bottom_left  = LSFmod(AudioDubStep, strength = 200).crop(0, 540, -960, 0).Spline64Resize(900, 800).AddBorders(380,0,0,0)  # bottom left
bottom_right = LSFmod(AudioDubStep, strength = 200).crop(960, 540, 0, 0).Spline64Resize(900, 800).AddBorders(0,0,380,0)   # bottom right
blank        = BlankClip(AudioDubStep).crop(960, 540, 0, 0).Spline64Resize(1280, 800)
blankHalf    = BlankClip(bottom_right).crop(0, 360, 0, 0)
blankFill    = BlankClip(bottom_right)#.crop(0, 400, 0, 0)
blankquarter = BlankClip(blankHalf).crop(0, 220, 0, 0)
blankCorner  = BlankClip(top_left)
column1      = StackVertical(blankquarter, blankquarter, blank, blank, blank, blank, blankquarter, blankquarter)           # half the width
column2      = StackVertical(blankquarter, blankquarter, blankCorner, top_left, bottom_left, blankCorner, blankquarter, blankquarter)
column3      = StackVertical(blankquarter, blankquarter, blankCorner, top_right, bottom_right, blankCorner, blankquarter, blankquarter)
column6      = StackVertical(blankquarter, blankquarter, blank, blank, blank, blank, blankquarter, blankquarter).crop(400,0,0,0)  # 800
column5      = StackVertical(blankquarter, blankquarter, blank, blank, blank, blank, blankquarter, blankquarter).crop(0,0,-240,0) # 480
step5        = StackHorizontal(column6, column1, column2, column3, column1, column5)
return (step5)