Thanks for the info. So after 72 hrs if still no confirmation one can do a resync of the wallet to get rid of the transaction?
Using the resync flag just scans the Blockchain for additional confirmed transactions that may have been missed by the client. This does not remove the unconfirmed transaction.
-zapwallettxes removes the unconfirmed transaction.
Given that your client or anyone else do not rebroadcast, you can spend the output and likely have no problems having it propagated throughout the network.
Hopefully most of the network will drop it too. If no resync is done, that unconfirmed tx always in the wallet?
Nodes can have different policies and they can alter the timing when the transaction gets removed from their own mempool. By right, it should be removed in 72 hours. I haven't really experiment with an unconfirmed transaction but by default, Bitcoin Core rebroadcasts the transaction automatically.
I don't think it would be removed by Bitcoin Core automatically however.
Please lock the thread if there isn't anymore questions