Cash, 6 Players
Poker Tools Powered By Holdem Manager - The Ultimate Poker Software Suite. View Hand #37601926

Hero (BTN): $1.58 (79 bb)
SB: $4.15 (207.5 bb)
BB: $2.01 (100.5 bb)
UTG: $1.56 (78 bb)
MP: $4.30 (215 bb)
CO: $0.89 (44.5 bb)

Preflop: Hero is BTN with 9 T
3 folds, Hero raises to $0.06, SB folds, BB raises to $0.18, Hero calls $0.12

Flop: ($0.37) 8 4 J (2 players)
BB bets $0.16, Hero raises to $1.40, BB folds

This was not the first time this villian 3bet my steal.
I think in this spot the best options are: shove>fold>call.

First things first, make sure you got a 100bb stack. Secondly, I think the jam is ambitious in that 3bet pots tend to have less fold equity since their range is inherently stronger, especially at 2nl. I would prefer to see you check call here and try to realize your high equity. I understand the rationale that you don't have any showdown value and thus we should be realizing fold equity too, but I don't think we have enough FE at a 2nl 3b pot to make that the best play. I think a lot of players in this player pool will cbet almost all of their hands and then split their range on the turn between checking and firing again. If BB checks turn, we can jam there and realize more FE I feel, whereas if he barrels we can call twice depending on sizing.

I think you have enough equity with the combo draw for me to say that folding flop would be disastrous.

I think this shove is viable with this stacksize.
If we assign V a range of JJ-AA here we have 50,7% equity.
This combined with the FE we are getting and the fact that there is already money in the pot makes the shove a viable play imo.

Given your stack size I agree with the shove. Buy in full and a normal raise/call a shove otf is fine.