It’s kind of disappointing that there aren’t more Kinnikuman characters being made for Mugen. I mean Terryman and Buffloman alone would be perfect for anyone’s roster.
I can confirm that a large reason there isn't many Kinnikuman Muscle Fight ports is because Fighter Maker 95 sprites are notoriously difficult to rip, I believe there still isn't even a consistent method to do it. As for why there aren't more arrange edits like Descolor's M.U.S.C.L.E NES Kinniku and Robin Mask, or the 3D Pentaman and Zeburaman, anyone's guess. I agree would love more Kinnikuman characters.
Its very hard to port them over on a side note given they do a lot of very strange things that isnt particularly easy to code out. Especially the fact when they also come pretty jam packed with a lot of things in it.