Bike of that caliber most would have power which has that included id say. If going old school tech for cadence etc I think garmin still do one ? Used to be a gsc10 or something before they updated to make it go on the hub.

As mentioned, I suspect most people will have power from pedals, cranks or spider that gives cadence. However, Garmin do a magnetless cadence (and hub speed) that would work for you.

Garmin Cadence Sensor 2 | Bike

ETA: May want to just check the clearance between crank and chainstay. My SC is still on it's way, but noting people fit powermeter cranks with 'pods' on there I am assume the cadence sensor should fit. 9mm is what you need.