A ufotable screencap, i recommend you to use the LoHA if you wanted better results

I haven't tested much the LoRA version so you'll have to find out yourself how to use it, and honestly i don't know what's the suitable model for it. Use ESRGAN or latent upscaler with it, it was A test on training on 896x896 and a new config

I recommend you to use the LoHA

Recommended weight for the LoCon and the LoHA: 0.3~0.45 if you didn't fate artstyle to take over the character you want, keep it in your mind that most of Dataset was gathered from fate, i recommend 0.3 the most. It works good, for upscaling use ultrasharp-4x with denoising 0.3 & Tiling [Multidifussion] Method

0.5 and above if you want to do a chara in fate style