Discuss with your husband. Ask him what kind of arrangements will be ok for both sides. You definitely won’t be able to please both sides but what else can you do? Can’t simply cut baby in half right? So do what’s convenient for you and your husband and don’t bother about what the other person thinks.
For example to be fair, Mon-Fri stay at your own place. Sat at in-laws. Sun at your parents. Both houses probably can stay whole day but don’t need to overnight. If you’re like me, don’t have a house yet, decide which house you want to stay at the most, say 4 nights. Then 3 nights at the other house. Then following week, switch. Or stick with the plan for the time being.