I'm going to answer the question first: No, it is not possible. There is a grunt blocking the entrance to Seafloor Cavern, who tells you to go fight TEAM MAGMA.
Now, I'm gonna apologize. Apparently my PC has some virus and won't let me run OBS so I'm using images instead. Also, if these images lag the page too much, I'll remove them and leave links to them instead.
In your situation, you go to the Mossdeep Space Center first to fight team Magma without fighting Maxie.
I triggered the above cutscene first, entered the Mossdeep Space Center without fighting any of the minions and proceeded to the Seafloor Cavern:
As you can see, Team Aqua is already here and the Submarine they stole is sitting outside of the Seafloor Cavern still. Upon going to shore, however:
This grunt blocks the entrance to the Seafloor Cavern. It isn't a cutscene; he simply stands there giving dialogue hinting to go back and fight team Magma in Mossdeep. He faces North and turns South to face you when you talk to him.
This is all he says:
I remember your face!
If you're here, it must mean that you're about to mess with us again!
A punk like you, do you really think you can take on TEAM AQUA?
I'd say you're too early by about a trillion years!
You're a perfect fit for the likes of TEAM MAGMA!
Speaking of TEAM MAGMA, I hear they were spotted near MOSSDEEP.
That bunch of goons, they sure don't look good near the sea!"
If spoken to after this, the dialogue replays at "A punk like you..." to the end again.
He doesn't move until you defeat TEAM MAGMA in Mossdeep, so there is no avoiding the battle with Tabitha and Maxie without cheats.