What are the triggered unlocks for Buganda, Japan, and Mughal?

The information on how to trigger unlocking those Civs in a playthough is not currently on the fandom wiki, I was wondering if anyone could provide the information.

Mughal is also missing what Civs can lead into it. I know it hasn't been officially revealed yet, in case an embargo prevents people from telling.

I was working on a spreadsheet/flowchart of the various unlocks, but it's not that helpful if it's missing information. I'm also struggling with how to demonstrate unlocks from Antiquity Civs to Modern Civs, but I'll figure that out eventually.