The solution ?
Just fit Anafi propellers on the Mavic Air! It "enough" is a bit optimistic, handling is not easy. But this video by Masashi Imamura shows how to do it. The video also shows the difference in noise, obvious from a distance, and a measure of autonomy (which seems to be a little less than that observed with the original propellers, see here). Are you going to try this improbable DIY?