Bassline303 (12/7/2022)
Could be Realtime Anti Aliasing (TSR). Should look ok when sequencer or animation is running but when you stop it you can see ghosting sometimes.
You can change the AA in the project settings of UE5. (Default is TSR)
When rendering it should not be ghosting but you can also increase the quality of AA in the Render Q settings.
Have a look in this video (skip to 18.15 min)
Thanks again, solved.