I believe that everyone in my group took an ASI at 4th level. The group dissolved due to people moving before we reached another level where feats could be taken.
Alert
Crossbow Expert
Defensive Duelist
Dual Wielder
Elemental Adept (fire)
Great Weapon Master (3+)
Lucky (3+)
Mobile
Observant (by someone who hadn't seen the "passive" part, but it was still decent)
Polearm Master
Resilient (4)
Sentinel (2)
Sharpshooter
Shield Master
Tough
Resilient and Tough were only ever taken at high level.