Can I for example import a static mesh and then add an existing skeleton and animation to it?
So that some of my meshes could just have the same animation?
If yes how could this be done?
No. Your mesh needs to have be skinned to a skeleton(meaning it needs to be a skeletal mesh) first in order to be able to share animations with other skeletal meshes. Check here to get more info on animation retargeting between different skeletons.
Thanks you !