Flashing the requires Tasmota32 Solo1 build is covered in Digiblur's blog post https://www.digiblur.com/p/linkind-esp32-smart-switch-how-to-flash.html
I am using a custom compiled firmware that includes all device group features, full rules features, TasMesh, and BLE. (Using TasMesh and BLE on this single core ESP32 may be unreliable. TasMesh is still a WIP.)
Follow digiblur's instructions to flash whichever variety of Tasmota32 Solo1 you want, but the following is only confirmed to work on the 9.5.0.9 commit 1b0de24. Come chat in the discord if you want to compile your own bin https://discord.digiblur.com/