I don't know an awful lot about Monzo to be honest so couldn't say for sure.
I got a Revolut account without any invite. Set up your account via the phone app and then order a card from them (£5). Set up some accounts to top up from. Done.
The main difference for me is that its a multi currency card.
You top up in £, use the app to convert it to the currency you are using at interbank rate and then when you are abroad the card purchases you make are automatically taken in that currency. no charges per transaction and the best rate.
Nah, don't bother. Just get a Revolut. Done.