Make a Ulysses pact
A Ulysses pact is a term used to describe commitment strategies. By binding himself to the mast, Ulysses prevented self-destruction. In a similar way, you need to consider what the Ulysses pact for your team is. The pact I recommend is to institute a simple principle everyone can hold each other accountable to.
“Meetings as the last resort - not the first option.” - David Heinemeier Hansson, Basecamp
The biggest obstacle to asynchronous work is meetings, which by definition are synchronous. By agreeing to this basic pact, you can help the team think consciously about the meetings that are absolutely necessary.