RPG based on Might and Magic.

It's quite possible :) In my opinion, Canigiem brought in characters like Alamar, who didn't age in 70 years, to fill such gaps. Fortunately, he had very few of these gaps (mostly amusing situations, like different characters with the same names – 2 Crag Hack, 2 Sandro, and 2 Etric – but these aren't inconsistencies). But I disagree with you about Axeoth. Of course, the 3DO developers embellished a lot, but it fit with Canigiem and Gravell's (the author of the books that first introduced Axeoth) ideas. By the way, in the action series (Crusaders, Warriors, Shifters), 3DO correctly used Canigiem's ideas, which were developed in Crusaders.
I suggest the following options for the setting:
1. Axeoth after the events of Heroes 4 with the expansions and Heroes 9 (but following the NWC style as much as possible).
2. Enroth, where the Reckoning didn't happen (there are many possible plot developments).
3. Enroth without the Reckoning, but also without the Chronicles.
4. Identical to point 1, but without the Chronicles.
5. Enroth after the Reckoning.
6. Xeen (again, many possible plot developments) and some other of the worlds mentioned above.

Added 2 minutes ago

I agree with you, although Axeoth isn't hopeless yet. I'm the main plot creator in Regeneration, but Enroth without the Reckoning, and ideally without the Chronicles, is my dream (on the scale of a campaign and the internet).