a. That guide, won't work with current vsrealesrgan.
b. Assuming you use Vapoursynth R57 and not the new Vapoursynth R58 the steps I posted over at
https://forum.doom9.org/showthread.php?t=184000 should work.
Using VapourSynth R58 would require to use Python 3.8 (not 3.9 or 3.10) since R58 only supports 3.8 and 3.10, but onnxruntime does not support 3.10 atm.
Cu Selur