DualWield Plugin
Dualwield is a simple lightweight plugin that adds onto the already existing dual-wield feature thats implemented into minecraft itself, this adds the ability to mine/attack with the item thats in your offhand!
I think its very useful and should be added!
Note: if this was suggested and denied or anything, forgive me because I do not know if it was or wasnt.
Link:
https://www.spigotmc.org/resources/dualwield.82349/