What are all the world chess championships (such that...)? Wiki says: Magnus Carlsen is 'the current World Chess Champion, World Rapid Chess Champion, and World Blitz Chess Champion'. Wesley So is 'current World Fischer Random Chess Champion'.

What world chess championships are both Magnus Carlsen and Wesley So eligible for (aside from possibly World Championship of Chess Composition, World Chess Solving Championship and World Team Chess Championship aaaand world women's in case fide allows transgender)?

I wasn't able to find a list of world championships in chess except for the wiki one:
https://en.wikipedia.org/wiki/Category:World_championships_in_chess
One reason I'm asking is that I want to clarify my understanding:

Magnus Carlsen is the world chess champion in every possible standard category. He is the world chess champion in every possible category except chess960. Wesley So is the world chess champion in the only category that Magnus Carlsen can be but isn't. (The previous sentences exclude World Championship of Chess Composition, World Chess Solving Championship and World Team Chess Championship.)

Please correct if I misunderstood something.

Where can I find an official list of world championships in chess? I mean, the one above is just wikipedia. Idk I just figure FIDE might have some list on its site somewhere.
Where can I find an official list of world championships in chess? I mean, the one above is just wikipedia. Idk I just figure FIDE might have some list on its site somewhere.

The closest official FIDE list is in section D. REGULATIONS FOR SPECIFIC COMPETITIONS of The FIDE Handbook. There you will find many subsections specifying the regulations for all the different competitions that FIDE organises.
For most of them it is obvious whether both players qualify. For example, neither of them qualify for the various age-limited world championships for juniors and seniors (detailed in most of D.04).
Slightly more difficult is to decide whether or not a competition qualifies as a World Championship. Your mileage may vary. For example I would classify the FIDE World Cup (D.01.03) as the World Knockout Championship. It isn't classified as a world championship because many people think knockout is an unfair form of competition - too much luck of the draw.
Section D.07 has the regulations for the world open rapid and blitz championships and D.08 for Fischer Random.