Bitcoin-Safe.org desktop enable this exact use case thanks to the Chat&Sync functionality. Chat enable coordination throughout in-app secure encrypted messages. The Sync allow transactions and addresses categories and labels to be sync across multiple signers of the same multi-sig wallet. Both powered by nostr.

All this wrapped in a open source protocol built by @Andreasgriffin. Satsigner.com wallet is adopting this protocol to enable the same functionality on mobile.

Really soon: Bitcoin Safe will release v1.5 with a lot of improvements and new functionalities

Stay tuned!