KingTubb
I believe the official consensus is that “Paper Mario”, “Baby Mario” and Mario from the “Mario & Luigi” games are different Marios to “Main Mario”.

It would be interesting to try to categorize which Mario games star a specific Mario and which other Mario games are clearly differentiated.
Like, “Donkey Kong”`s Jumpman is the same Mario as the one in “Wrecking Crew”, “Golf” and “Pinball”, but “Dr. Mario” and “Mario is Missing” are clearly different invididuals. “Super Mario Bros. 2” is not canonical, never happened, but Mario from “Mario+Rabbids” is Main Mario.