Dragon Age II is the black sheep of Dragon Age family but it made its way to Xbox One. Origins received backwards compatibility treatment in 2017 and Inquisition was launched on current-gen consoles so Dragon Age trilogy is now complete.
Dragon Age II marked one of the biggest devolutions of its time as BioWare mercilessly ripped out a pile of RPG elements that were present in Dragon Age: Origins and drastically changed the game's art style. This sent Dragon Age fans into a blood frenzy which quickly resulted in them ripping the game to shreds.
On the flip side, BioWare improved the combat system compared to Origins. The end product was not a bad game, as I still had fun playing through but it left a bitter taste of betrayal behind. Fast forward seven years, BioWare's life hangs by a thread and barely anyone even knows about the Dragon Age II controversy, all thanks to a series of rushed out releases, and Mass Defect Andromeda.
Compared to BioWare's later flaws, Dragon Age II's shortcomings look minute so it may make sense that players can now buy it for Xbox One. It's not as good as the other two entries in the series, but it should still provide a fun playthrough. Dragon Age II's price tag sits at £14,99 or $19,99 so it's not a high price to pay for 30 to 40 hours of decent gameplay.
The Xbox One store page is littered with DLC for the game that could potentially pump the price up but none of it is really necessary. If a player is inclined to expand the play time or otherwise spend money on the DLC, Legacy would be my top suggestion as it ties into Dragon Age: Inquisition story.
BioWare have recently announced that Anthem will have a strong narrative that was typical for older BioWare titles but it remains to be seen if a looter shooter with power armours can come anywhere near Dragon Age: Origins, as even its first successor failed to keep up.