>>2826226Highres fix behaves differently from other upscaling methods, you're gonna have a hard time replicating it. Personally, I do highres fix first, then send it to img2img and do tiled diffusion at 0.3-0.4 denoising.
It helps to remember that tiled diffusion is just img2img on each individual tile. Here are my tiled diffusion settings for what it's worth.