What is the problem?
If a player move towards another player a collision occurs with the other player.
Sounds like a reasonable thing to happen no?
The character movement component will in general move with the base it’s standing on. So as long as the player is standing on a valid base I would expect collision to work normally.
What is a little bit problematic is jumping on moving platforms. What I added in past projects was that I keep the connection to the base active so that the player keeps moving with the speed of the platform. Was used for example to stay in sync with a moving train.