I’m looking for an MR16 form factor, GU-10 base, RGB LED bulb with wif-fi interface that has a WORKING integration in HA. (I don’t think Magic Home works with HA anymore).
I know there are a million bulbs on Amazon. The trick is finding one that actually works with HA. Best of all would be one that does NOT require yet another phone app and is either from a vendor I already use, or works through SmartThings.
How about the Ikea GU10 which is quite cheap but you will need a Zigbee USB dongle:
If you had a bunch of these to control in a large room then you could do this at the switch instead with your existing lights using something like a Shelly behind the switch.
I use Miboxer/Mi-Light GU10 RGBWW lamps. They are not wifi, you need a Miboxer hub, but they are very reliable and work fine with HA using the LimitlessLed integration.
It’s not exactly, what you asked, but mention worthy… 
Well there’s two ideas, but not really wanting to add supporting hardware for just one bulb. I’m already into Z-wave.
Athom uses wifi bulbs.
Athom looks interesting. Not clear from the picture if it’s really an MR16 but they’re not expensive.
