@PerfsPC I might expect some jittering at higher speeds, but you’re hardly even moving in that video so I suspect something is wrong, like the position being set on non-owners or something so it’s fighting with smooth sync.
To disable UE4 replication and enable Smooth Sync you disable Replicate Movement on your Actor and add the Smooth Sync component. BTW we have a discordwhere you can ask questions and maybe get a quicker response.