Don’t know if its a bug or a feature that didn’t get fully changed in descriptions but there are some bugs with Void Cleave proccing Abyssal echoes. Firstly Abyssal echoes seems to proc Nether coating when cast this way despite the wording say when you DIRECTLY cast abyssal echoes gain nether coating. Secondly Abyssal echoes also proc from your Void cleave echoes despite it being YOU cast abyssal after void cleave. This second Abyssal echoes also costs mana and procs Nether coating as well.
Weirdly I feel it is a really nice QOL and somewhat balanced rn as you need to manage the big Mana cost of Void Cleave+2Abyssal echoes.