From the OT FAQ
Q : When was the last detection?
A : As of now, Onetap has never been detected yet.
Q : Which anti-cheats does Onetap support?
A : As of now, we only provide official support for Valve Anti-Cheat (VAC), SMAC and the FACEIT Serverside Anti-Cheat (not the client), however a more extensive anti-cheat support might come as the developer improve the product.
Hope this helps in anyway!