Certain things don’t populate across various client apps because they’re only stored locally, instead of being broadcast out to relays. Your custom feeds in Primal and Nostur won’t populate over to other clients, for instance. But your other profile info should, such as your username, profile pic, Lightning address, nostr address, following, etc. Basically, anything that gets broadcast to a relay should appear in other apps, as long as they support those features. But if it’s a local-only feature/setting, then it will only be in that app.