Originally Posted by S2PHANE
Huh, in Early Access only Shattered Flail that you get from the gnoll fight on The Risen Road comes to mind.
https://baldursgate3.wiki.fextralife.com/Shattered+Flail

Unfortunately the Shattered Flail isn't a club. It's a mace. So even if you can equip it, you won't be able to cast Shillelagh on it.