annoyedmom1 You said:
I think a big problem is my husband sees them as good people and wants my kids to be close with them. He wants them to babysit and have sleepovers.
So the "big problem" isn't with "boundaries" or your your husband, or PIL; it's with you. And from what I extrapolated from your OP, your resentment of them has its roots in your jealousy of your sister in law and the time, money and attention that your in laws bestow on her.
His family throws fits and demands time alone with the kids. His parents want us to drop the kids off 4 hours away at their place.
This is a bit of a drip feed because in your previous posts, you've never mentioned them wanting "alone time" with your children or that they expect you to drop the children off at your expense.
You said If they were willing to come here and watch them they would be welcome but, on 05.01.2022 @ 23.12 you said I don’t allow babysitting or sleepovers which somewhat contradicts your willingness.
Just my personal observation, going off what you've told us; your bitterness, anger and resentment stems entirely on your jealousy of how your PILs are financially more generous towards their daughter. This doesn't seem to be as much of a problem to your husband as it does to you and, as you've admitted that he wants his children to have a closer relationship with their paternal grandparents, you're in danger of coming unstuck if you continue to use the children as a weapon against them. Try looking beyond the allocation of money, who pays for holidays and travel and who buys birthday presents for who...... concentrate on what's good for the children.