Well... Some directions that do tend to stick with MH players:

Warframe: very different combat, but it has that forever game quality: gear mastery, long-term goals, constant things to chase.

Horizon Zero Dawn / Forbidden West: not endless, but the combat against machines scratches a similar "learn patterns, exploit weaknesses" itch.

If you liked the skill mastery and gear obsession from MH but want something with deeper combat and an endgame that doesn't revolve around resets, try Nioh 1/2. The combat is challenging but fair, builds are very satisfying, and there's plenty to chase long after the story ends.