I don't know if I can since I'm new to speedrunning. And I realized there's a typo in my question "the" is supposed to be "then"

Provided the run complies with all the restrictions for both categories, you should be perfectly able to upload the same run to more than 1 category.

If you still have doubts about it though, you could try asking at the forums of the game you're trying to run (or you could also DM the mods of the game I guess).