TPWD:
AUSTIN- The private recreational angler red snapper season in federal water opens Wednesday, June 1, 2022. Red snapper fishing is open year around in state waters. Bag and size limits will remain unchanged. The regulations are 2 fish per person daily with a 16-inch minimum size limit in federal waters, and 4 fish per person daily with a 15-inch minimum in state waters. Red snapper caught in federal waters count as part of the state bag limit of 4 fish. No more than 2 red snapper in federal waters and 4 red snapper in state waters may be in your possession while fishing.

Question:
So when you come back to the dock, and each person has 6 snapper in the cooler, you are OK with the Warden because 4 of those fish were caught in State Water and the other 2 were caught in Federal water.

Am I reading that correct?

NO! This is very simple. You cannot have more than 4 red snapper in your possession while in state water including the dock. It doesn't matter if you are fishing or not. Possession is the key. Likewise, in Federal water, you cannot have more than 2 red snapper in your possession, no matter where they were caught, so don't catch your 4 state snapper then head out to Federal waters.

The rule says "2 red snapper in federal waters AND 4 red snapper in state waters".

If you couldn't have both state and federal fish in the boat wouldn't the rule say "or"? Ex: 2 Federal Water fish or 4 State Water fish in your possession....
Since the rule used the word "and", it leads me to believe that you could have both.

Well you believe wrong.

Unfortunately, regulations are becoming more complicated and confusing. The wording can be interpreted in different ways, but if you encounter a game warden they will explain that you cannot have more than the state limit when in state waters. So it is 4 red snapper. You can catch all 4 in state waters or 2 in federal and 2 in state. If you think about it, this is the only way that the regulation is enforceable.

The rule uses "and" because both conditions must be true. The limit in Federal waters is 2 AND the limit in State waters is 4. I highlighted the sentence that clears this up

https://tpwd.texas.gov/newsmedia/releases/?req=20220506a

"AUSTIN- The private recreational angler red snapper season in federal water opens Wednesday, June 1, 2022. Red snapper fishing is open year around in state waters. Bag and size limits will remain unchanged. The regulations are 2 fish per person daily with a 16-inch minimum size limit in federal waters, and 4 fish per person daily with a 15-inch minimum in state waters. Red snapper caught in federal waters count as part of the state bag limit of 4 fish. No more than 2 red snapper in federal waters and 4 red snapper in state waters may be in your possession while fishing."

Zeek clears it up pretty well with the sentence he highlighted.

Thanks Zeek

For each license holder, or exempt, they have to catch the 2 Fed Snappers first then come back for 2 state water on the way back in. If you have more than 2in possession in Fed waters that’s a violation. More than 4 in possession in state waters that’s a violation.