That's a tricky one. Normally in that situation there's a person in the back swapping your guitar for a tuned one.
If all you have on stage is your guitar with a wireless then you can't choose any other option.
If you use active pickups you may be able to insert a tuner with cables to and from a tuner on stage, between the wireless receiver and the Kemper. Then the tuner will mute the input of the Kemper. Long cable run though...
If the gigs are not too huge you could use a Strobo Clip and just turn your guitar volume down.