Honestly at this point you'd have to mod so much I'm not even sure a 5e faithful replication is possible, tbh. Either way, I don't see other game modes coming, no. I also have no idea what you mean about DOS2 having other game modes, tbh, because it just sounds like you're talking about the difficulty settings and that's... not the same thing. I just finished DOS2 a month or two ago and don't recall anything else, off-hand.
