Question about Legendary powers

On my Seasonal Monk, I have Bracers and weapons with the “Exploding Palm’s on-death explosion applies Exploding Palm. Exploding Palm’s damage is increased by XX%”.
Bracers increase by 86%, Main Hand increases by 425% and off-hand weapon increases by 418%.

My question is this. Are they additive giving me a 929% increase or does only one of them count?

Gungdo Gear is a separate multiplier from The Fist of Az’Turasq. Unfortunately you can not have both the Fist of Az’Turasq and your Bartuc’s with the Fist of Az’Turasq power. I don’t know which of the two will be the active power, but either the Bartuc’s or the Fist of Az will affect your EP’s.

Thank you.
So I’m getting Gungdo & one weapon because the weapons are the same.

Correct, ideally you’d replace the Fist of Az’Turasq with an ancient Lion’s Claw. Then I’d suggest you cube your Ring of Royal Grandeur (if you don’t have it cubed already) and swap the Ice Climbers and SSS belt for Captain Crimson set (that set is ideal for Uliana builds).

Your skill choices are very unoptimized. Beacon of Ytar is a must (20% CDR is very good and I’d swap out Exalted Soul). Cold EP has the highest damage of any rune. Windforce Flurry is decent but Assimilation has the most synergy. Mystic Ally is not very useful (plus you have the WORST rune), I’d swap it to Cyclone Strike (and cube Lefebvre’s or Spirit Guards). SSS should be Sustained Assault (more SSS means more dps). Desert Shroud rune will give you more toughness to keep you alive. Replace the amethyst in your helm with a diamond.