I dont have any information about villain.

OTF it's close, because you can raise for value against Ax or draws, but dont want to be allin on this flop. I think im almost crushed against his 3b range OTF. Fine?

The river is really close. We need 31% equity and all the flushdraws have missed and he can play AK(?) the same? Can we ever fold here?

PokerStars - $0.10 NL FAST (6 max) - Holdem - 6 players
Hand converted by PokerTracker 4

BTN: 100 BB
SB: 104.1 BB
Hero (BB): 100 BB
UTG: 101 BB
MP: 102.8 BB
CO: 183.4 BB

SB posts SB 0.5 BB, Hero posts BB 1 BB

Pre Flop: (pot: 1.5 BB) Hero has J 9

fold, fold, fold, BTN raises to 3 BB, fold, Hero calls 2 BB

Flop: (6.5 BB, 2 players) 9 J A
Hero checks, BTN bets 4 BB, Hero calls 4 BB

Turn: (14.5 BB, 2 players) Q
Hero checks, BTN bets 11 BB, Hero calls 11 BB

River: (36.5 BB, 2 players) 4
Hero checks, BTN bets 31 BB

I'm okay with a flop check-raise for value on this wet board. Because villain opens from the button his range is not smashing as flop all that often, and there are some pair plus combo drawers that villain could get in on the Flop with, so you are not necessarily crushed if villain 3 bets you on flop.

The bet sizing villain uses on the turn makes me think that the queen has helped him. I would be making a snug fold on the river expecting to see Ace Queen or King 10 or queen Jack. Ace King is possible.

If you look at villains range to bet this amount on the river I don't think Heroes Equity is good enough to make this call because villains range is mostly sets straights and larger two pairs