Ranger-Hunter; Multiattack feature. It’s one attack with multiple targets and multiple attack rolls. How does it work with spells with “The next time you hit a creature with a weapon attack before this spell ends” (like Ensnaring Strike)? Choose one? (1/2) What about Absorb Elements? "Also, the first time you hit with a melee attack on your next turn, the target takes an extra 1d6 damage of the triggering type, and the spell ends." Additional damage to all? (2/2)

— kentusrpg (@kentusrpg) November 2, 2018

In D&D, attack rolls are assumed to be sequential, rather than simultaneous, unless a rule tells you otherwise.

If your DM prefers the attack rolls of your Volley/Whirlwind Attack to be simultaneous, choose the creature affected by ensnaring strike from among those hit. #DnD https://t.co/G2iRNsCq67

— Jeremy Crawford (@JeremyECrawford) February 1, 2019