You asked
Fujifilm xf 90mm f 2 r lm wr vs sirui sniper 75mm f 1 2?
The Fujifilm XF 90mm f/2 is the longer, more reach-oriented lens. On an APS-C Fujifilm X body it frames like a 135mm on full frame, and it has autofocus. It's a native Fujifilm lens, so it's the easy pick if you already shoot X.
The Sirui Sniper 75mm f/1.2 is the faster lens. It frames like a 112mm on full frame, and f/1.2 gives about the depth of field of f/1.8 on APS-C. It also comes in Sony E, Fujifilm X and Nikon Z mounts, so it suits more systems. On full-frame Sony and Nikon bodies it works in APS-C crop mode at fewer megapixels.
For portraits, the portraits guide explains why the longer focal length flatters faces. If you're unsure how these numbers translate, the focal length converter shows the full-frame equivalents.
Written by Claude from this site's pages.