Introductions, Any Advice Is Great!

Sorry guys, dunno how to turn the photo around lol
So we set up some gates for the boys to try and get them to more accustomed to each other. They play through the gate, but it keeps escalating from happy rolling over swats to angry swats. Any way to avoid this that people can think of?

Here are some articles:

Are My Cats Fighting Or Playing?
How To Successfully Introduce Cats: The Ultimate Guide

I think it would be best to separate the two if they start getting cranky at each other. They might just need a break from each other for a little while. Play smacking is common and can look aggressive but it's all for fun. If one or both are hissing and growling while smacking, definitely separate both for awhile.

Yah, I know it can be hard to tell sometimes lol and there's never any growling or hissing, but I can just tell George is stressed, and I dont know of he's stressed because of the play escalation or because he can't get to Oscar and he wants to.

He can be a brat when he doesn't get his way.

I don't know the exact percentage, but play is very often unequal. Meaning the cats start out playing, one decides it has had enough, and hisses, growls or just tries to run, and the other persists for a bit. And, very often, the one that disengages first, will be right back with the other cat, acting like nothing happened, maybe even wanting to play again. Since there are gates up, that may or may not be what is going on -- it could be that one of them is careless with nails perhaps. So take a look and trim if needed.

But most likely they are ready to be put together and let them try to complete the process on their own. You often can't get to 100% with a careful controlled process. They need time. And even if things are on track, there might be some stress, growling, hissing, swatting. As long as there is no actual fighting.

Try feeding them treats when they're on either side of the gate, to try to make being in each other's presence a positive thing.

I learned that too, giving them delicious treats when they see each other
they will associate seeing each with good things!
I think they are doing pretty good, keep it up!
Just some time and patience will do it!

Unless they are hissing, growling or have ears totally flat against their head, it's not angry swats. We had to get used to this two when we added our second cat. Cat play is quite rough. The swats are likely fine, but if you want to take a video and upload it so we can see please do so.

It looks to me like you're nearly ready for some supervised playtime with them in the same room.

I don't know who is who, but those are some nice looking cats
It might be a moment in time on a camera and nothing more, but the predominantly white fluffy cat is looking at the predominantly black cat, who is doing a pretty obvious look-away. That to me is a sign of a cat saying "I don't want any trouble." If this were a real fight waiting to happen, they'd be in a tense stare down. It looks and sounds like curiosity and boundary setting.
I'd make gate-less greetings short, sweet, and don't wait to separate until something goes bad. Separate them after a minute or so while they're still getting along and investigating so they leave on a positive note, eventually they'll leave one another wanting "just another few minutes, mom!"
The last thing you want is to have one cat get really mad (not just annoyed) and then have the other cat taken out of the room, and leave them with that feeling of adrenaline focused on the other cat.