Do 2 of the same weapons procs both work? Say if I used 2 stormhearts, would both chain lightning active ? Or what about 2 brutallax, does the bleed stack from both ?
They can proc independently, for Stormhearts at least. Not too sure on Brutallax though and similar stuf though-.
As the Brutallax effect is an attack that applies a bleed (rather than a debuff that applies a bleed per second) I’m going with yes* you can stack two Brutallax procs onto one target. It works with poison weapons like Plaguebearer’s and it even works with component non-procs like Mark of Dreeg where you can tag an opponent with two procs or dreeg casts and as long as their originated from different items the dots stack.
*I have not tested Brutallax specifically but other items with the exact same wording work fine. Should be able to stack the effects from 2X Bloodsong too.