With historic cars we enable the auto-clutch option in the servers of our Club Races, because many drivers are using paddles shifter, and they deserve to have the same conditions of the other drivers that use manual clutch and manual heel&toe.Damn bad time to have the clutch pedal die on me
So if you enable the auto-clutch and the auto-blip options in your Assetto Corsa realism settings, the server will accept both of them and you'll be fine with 2 pedals as well.