Animating player and separate object in the same animation

My goal is to make a system that allows the player choose a “mount”, which is essentially an animal that they will ride instead of walking around.

I have the animals done and animated in blender. The problem is that I need the players’ movement to be a part of the same animation (correct?).

How can I animate a Roblox character along with the animal inside blender, and then export it in a way that makes it work with any player’s roblox character?