You asked
Fujifilm xf 16 55mm f 2 8 r lm wr vs fujifilm 16 50mm f 2 8 4 8?
The 16-55mm f/2.8 is the one I'd point most people to if they want a constant f/2.8 standard zoom on an X-mount body. The site describes it as the first of its kind for the X system, and it's larger and heavier than the II version. On APS-C it frames like 24-82mm and gives about the depth of field of f/4.2 at f/2.8.
The 16-50mm f/2.8-4.8 is a variable-aperture zoom, so it only reaches f/2.8 at the wide end. I don't have its full specs on the site, so I can't say how it compares on size, weight or price. Check its page for details.
If you're shooting landscapes, where you'll mostly stop down anyway, the landscape guide explains why f/4 zooms can be the smarter buy. For more on the 16-55 line, see the 16-55mm II page.
Written by Claude from this site's pages.