Make DC fan smart?

I bought a house that has three ceiling fans. Each have a dumb wall switch and then a remote to control the speed/light. I expected them all to be AC powered so I was going to use Inovelli switch & fan module, but they are actually all DC powered.

I want to control them from in HA but also have a smart wall switch for guests, etc which at least turns the fan on/off (not too concerned about speed/light via the switch).

My options seem limited tho. I found Bond Bridge but not sure how well that works and that still leaves what to do with the wall switches.

Any suggestions on the best way to make these smart?

You should describe little better the circuit. They have AC/DC converter built in? Switches are wired to AC or DC? DC voltage? Amps?