I wouldn’t recommend it.

I don’t think it will save time as there would be an element of CPU time, RAM swapping, and hard disk thrashing, etc. depending on system specs and the amount of data to be scanned in both scans.

I just schedule an avast Quick scan at a time when I know the computer will be on and not generally busy, following that up 15 minutes later by an MBAM Quick scan. On my system both of these Quick scans only take a few minutes each (MBAM being slightly slower).