Which touch switches still work with SonOTA?

Are there any switches that still flashable with SonOTA?
If not, how hard is it to manually flash it with Tasmota?

i use tasmota on sonoff t1 us switches. 1,2 and 3 gang.
Open them up. 4 connectes gnd, tx, rw, 3.3v, connect to your ftdi connector and flash using your favourite firmware bin file.
Open termite, type in setoption13 1 and backlog wifi credentials. and you’re good to go

Connecting GND to R19/GPIO0 isn’t needed?

Just have a look here