Overview: For transfer animation from Maya to UE conclude 2 main parts. Export the Skeleton from Maya, import the skeleton mesh to UE Export the animation UE, Import the animation to UE
Export skeleton In the outliner, Make sure shift select meshes and skeleton/bones, we can choose the top group and use the select Hierarchy button to make sure all parts are included. If your character is rigged with controllers, make sure to exclude the controllers(curves), you would only want the bones, the goemetry(mesh), and the blendshapes).
Make sure your model is in T/A default pose and your root was placed at (0.0.0)
Open Game Exporter
(I recommend that you should always use game exporter for exporting FBX for Game engine )
Go to the model tab, Here is the setting
For exporting skeleton mesh, do not check the smooth mesh box, it might break your skinning
When exporting static mesh, it is recommended to check the smooth mesh box if you have a smooth preview turned on for your viewport. It saves a step to subdivide your meshes before export. I prefer to keep the unsubdivided mesh in the maya scene for dealing with iterations.
Skinning and blendshape must be checked here since it is for skeleton mesh.
I would keep Y up here. When importing to UE, set the convert scene there.
For the FBX version, I prefer to use a lower version like 2018
3. Import the skeleton mesh to UE
Mostly default setting
Make sure to check Use T0 As Ref Pose
4. Export Animation
Back to Maya>Game Exporter> Animation Clips tab
Game exporter allow you to export multiple clips at once
5. Import Animation to UE
first, uncheck Import mesh, select the corresponding skeleton
Sometimes you might end up with missing meshes after you import your model to UE.
It might be normal issues or more likely it is caused by the certain deformers your rigger used that is not support by UE.
Sometimes you might also end up with missing hair.
For a character who has xgen hair, that is another post.
Hope you find this helpful.