Is Cyborg a Teen Titans member or is he still a Justice League member?

Towards the end he becomes one

To me it seemed like he was a JL member but just went to hang out with the TT at the end

He may now have a split membership but the end implies he's a Titan now

When theres no more room in Hollywood, remakes shall walk the Earth.

By his own word he would never move down, so he remained in the JL, but since the titans are more fun he will hang out with them as opposed to the League and may work with them from time to time.

He sees JL as the major leagues so when they need him he will be there 1st. He much rather hang out with the TT since they are close in age.

Well at the end he says something about being tired of being the young one in the group and that it was awkward when the JL saw him with the TT.

Nest. Use it, live it, love it.

Cyborg is still a JL member. There is no indication that he left here and he is a JL member in Justice League Dark. All sorts of DC characters were on 2 or more teams at once in the comics. He can be a bridge between teams in the future.

He's gonna be like Wally was in the Crisis to Crisis era comics. Sort of both.