I have an AX1500 in Access Point mode and an EAP110, both connected to the same router.  About 1.5 years ago or so, I did a lot of testing to see if I could get some usable roaming between them, but it was not good.  There would usually be 1-3 seconds of static while switching AP's.  So I gave up on it.

But recently, there was a firmware update for the EAP110 that mentioned adding 802.11r.  And there had also been a few firmware updates on the AX1500, and I know it has OneMesh support, though I'm not using it.

EAP110-Outdoor(US)_V3_5.0.7 Build 20230410
1. Add support for 802.11r fast roaming protocol.

So I thought it was worth trying roaming again.  To my surprise, I was able to roam seamlessly between 2.4 & 5 on the AX1500 and 2.4 on the EAP110.  Tested with a voip call.  If there's a blip, it's mostly imperceptible.  Maybe 1 or 2 20ms sip packets dropped.

I took a look with WifiInfoView, but it doesn't show any support for 802.11r/k/v.  But I suppose it might not show up there.  I tried WireShark, but I couldn't get my wifi usb dongle to go into capture mode.

Is there any current info on what's really supported on these with the latest firmware?

I guess I'll add, it's been a long time, so it's possible there is something else I'm doing different now or misremembering.  And also, there have been many android firmware updates for my phone, so the client is different, too.  The SSID is set the same for everything.