Thx for your quick overview.
Well I planed a mysensors + FHEM network 5-6 years ago. but focus changed and other projects became more popular.

Now I’m working with HA + ESPHome with great success.

But ESPHome doesn’t support a simple wired network like RS485 or longe range Wireless communication.

Searching for a easy solution for some garden sprinkler and RS485 remote nodes, I found mySensors (again).

Just grabed a bunch RFM69 (already laying around) + ESP8266 for a gateway and ATMega Mini Pro’s for the nodes. And WOW using the Homeassistant Integration. It makes really fun.

It’s a pitty it’s not maintained any more