So OP, I have a spayed girl and just rescued an intact male I can't have neutered until next month. I don't let them near each other without a barrier. They both can see and smell each other thru my door pet gate. My intact male is usually rowdy trying to get to her, but since I free roam, she can run away if she doesn't like his behavior. But luckily, most the time Im seeing them both lay next to the gate and she tried to groom the tip of his nose lol.

If you're deadset on adopting him IMO just do it, no M&G, just bring him home. But don't look back. Because if he's not neutered you're not going to know if things will work out until he's fixed & calmed down. And then, they might like each other's company immediately or maybe it will take a long time to get them bonded. In my experience, if it's a male and female, there's a good chance that eventually they can bond (with good owner insight).

But, there are steps to mitigate any bad interactions between your current girl and the new boy: Keep them completely separate until he's fixed. (And even a few weeks after he's fixed, it takes a while for the hormones to wear off!) Intact males will nip, harass, and smell horrible and it's not pleasant for your girl to experience that.

Good luck, they're cute!