Villain is fairly aggressive, had been betting and fighting for pots postflop. I had already called them down on a bluff before (F ch, T donk pot, R donk pot w/ T high) I had AQ on scary board AJ779

Hero UTG+1 133.25BB
BU 208.5BB
BB 16.5BB
Hero is dealt TQ

Hero opens to 2.5BB, BU calls, SB + BB fold

Flop (6.5BB): Q2J
Hero checks, BU checks

Turn (6.5BB): 8
Hero bets 4.75BB, BU calls

River (16BB): T
Hero checks, BU shoves 126BB effectively

-I think I am a bit underrepped, should that effect my decision here?
-Should the overbet make me more or less likely to call? I had already shown I would call them down if he bet pot on R, so they may have decided to size up?
-are they/should they shoving with a straight here?

Beginner barely related question:
I had not been C betting in this game without position, is C betting a good play in general out of position? Seems like it could go very wrong if I get called, as I would have no idea where I am in the hand

This is often something that beats a nine trying to get max value out of nines. It's not really callable, and big deal you lost 7 bbs. Next hand.

As for c-betting, it's generally more important to c-bet when out of position, although villain's range, flop texture, and the character of your hand are more important things to consider. Be more inclined to c-bet oop with hands where you can have a plan for future action.

I wouldn't call it. He could have a flush or a set.

C-bet Flop, 2nd Barrel Turn.
The river card is ugly. His Range is very wide. Flush draws, 9x... everything is possible.
I don't see not so many busted draws in this spot.

I think there are two scenarios:
#1 Strong hands: Flush, Straight, Set (he failed to build a big pot and now he try to fix it)
#2 Nothing or very weak hands (hands without SD Value): A high, K high, 87...
With his other hands he often check behind.

You need so much equity for this call.
126/(16+126+126) = 47%

If you think he bluffs more than 47% of the time, close your eyes and push the call button
But I think, check/fold is the right move at the river!

You should fold vs jams like this OTR 99% of the time, only really calling with our strongest hands that beat some of villains value here. Flop and turn seem good.

As for cbetting OOP, you should be cbetting less than IP and checking more of your TPBK hands. This is because villain can force us to go 3 streets when we are OOP unlike when we are IP and can check back. Therefore we need to be checking back more hands that can call 3 streets but aren't quite strong enough to bet for 3 streets and QT is definitely in that range.

+1

im snapfolding everything below Khigh flush here.

Opening QTo in CO with a very aggressive player on BU is likely losing unless he is super bad. You get 3 bet a lot and rake on micros is insane