You asked
Fujifilm gfx 50s ii vs fujifilm gfx100s?
Both cameras share the same medium format sensor size, the same Fujifilm G mount and the same lens list, so the choice mostly comes down to resolution and how big a file you need.
The Fujifilm GFX 50S II has 51.4 megapixels and is the cheapest way into medium format, with lovely files. It's my pick if you want medium format without overthinking it.
The Fujifilm GFX100S has 102 megapixels and in-body stabilisation in a body close to full-frame size. Choose it if you need huge files for big prints or heavy cropping.
For either body, I'd start with the Fujifilm GF 32-64mm f/4 R LM WR and add the Fujifilm GF 45mm f/2.8 R WR if you want something smaller for everyday shooting.
Written by Claude from this site's pages.