So the Hap ax2 and ax3 can be powered via Poe.
Which is kinda awesome tech all on it's own

But I can only get it to work with a PoE injector and the original power brick that came in the box.
I'd really like to know which switch can power 4 to 8 of these devices all on it's own?

They both need 18-28 V and 1,2 A. And as far as I can see, I cannot find a switch that can power that much on it's own?

For instance this switch: https://mikrotik.com/product/crs112_8p_ ... ifications
can get up to 1A. But that is a bit too little.

Any suggestions?

I don't think you would have issues with the 1A, at 24 V it means 24W, whilst the Ax's are in the 12-15W range (without attachments), so you have plenty of leeway.

I would be more concerned with the total amount of power deliverable by that switch:
Max total out (A) 2.8A (18V-28V)

Given that there will be anyway some losses or peaks, if we consider 20W per device, 24V x 2.8A= 67W, so it is unlikely that you will be able to power 4 of them, more likely 3 at the most.

As both devices only accept 18V-28V, you clearly need PoE switch which does "passive" PoE and is powered with 24V (or there about) power adapter. Next you have to carefully read power specifications of both devices and consider how you're going to use them. If you'll use them as simple APs, then you have to look at "Max power consumption without attachments" which is 12W for hAP ax2 and 15W for hAP ax3. When power supply is at 24V, this translates to 0.5A for hAP ax2 and 0.63A for hAP ax3 (actual figures will be lower most of time, devices tend to draw maximum power while booting; also consider some power loss on cables if cables are not really short).