How does Uprising scale over the different difficulties?

Over the different difficulties, that is Normal, Hard, Expert, and Legendary, I am trying to understand how exactly Uprising scales over the 4 difficulties. I've discerned a few things although I am a little lost over other things -- I know that the timers do not change -- hack times and defend times do not change, and neither does the final 5 minute countdown to kill all 4 Orisas.

But what I would like to know is:

• How does enemy HP scale over the difficulties? It's clear they do much more damage at Legendary but I've never really grasped the scaled, is it 5 - 20 over 4 difficulties?
• Are wave mechanics affected? This is pure speculation on anecdotal evidence, but I think there seem to be far more splicers on Expert and Legendary as opposed to hard and normal. Does the same hold true for the Eviscerators and the Null Sector default robots?
• Is the damage we deal to robots affected on Legendary? It really does seem like it takes far more shots to kill enemies, although as stated previously, it could be down to increased enemy HP.

Essentially, I'm looking for an understanding of how difficulty scales across Uprising and what mechanics are changed, if any, from Normal to Legendary.

How does enemy HP scale over the difficulties?

The Health Points of the enemies is the same, no matter the difficulty.

Are wave mechanics affected?

The higher difficulty, the more enemies there will be. Plus, the AI will be more aware of your movements (for example, if you are covering the left they will come from the right and bastions will heal more frequently).

Is the damage we deal to robots affected on Legendary?

The damage that the players deal to robots is not changed. Instead, the robots make more damage on higher difficulties:

• Normal: 1.00x
• Hard: 1.30x - 1.40x
• Expert: 1.70x - 1.80x
• Legendary: 2.00x

(Please note that I don't remember the exact values of Hard and Expert, but on legendary they make the double of damage from normal)