Portals of Phereon [Syvaron]
https://f95zone.to/threads/portals-of-phereon-0-16-0-2-syvaron.7803/
"an exploration/ management/ breeding / turnbased (on tilemaps) strategy game with Monstergirls."
Futa on Male isn't main focus, but you can get it in the game by choosing male protagonist and interacting with futa characters.
- you can select two starting members of party and choose their sex (male/female/FUTA) and species (mostly monster girls, like centaur, mermaid, lizard, harpy, plant girl, etc.)
- at least two NPCs can be given a "futa potion"
- additional characters that can join your group can be futa as well
You can also choose futa protagonist, but I don't know for certain if it can lead to futa on male scenes.