Only a Warlock's perspective here, but possibly could effect other classes.
Arc Souls from Getaway Artist don't drigger Momentum Transfer. Also does not appear to work on Ashes to Assets. Arc Soul does trigger armament mods though, so it does count as a grenade to some respect.
The ranged Warlock Melees on top tree Dawnblade and middle tree Stormcaller don't trigger Impact Induction. Other ability melees trigged the mod though.
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Arc Soul is not a grenade. Ranged melees not triggering melee perks is a known issue.