"Merge Actors" tool causes animated static meshes to visibly hover around

Hey there! Whenever I’m merging the assets that got some kind of animation (e.g. vegetation that have waving root/leafs) they floating around in a weird manner - please see video. (1st tile is un-merged, and the second one is merged)

Not sure if this is a bug, seems to be tho. Any ideas for the workarounds? I could try to just place them in a regular manner in the BP, but I would prefer to have it as one mesh.

Thanks for any replies!