Cleat covers allow you to walk easily (though cleats are walkable to some extent anyhow) while also protecting the rubberized/plastic tips that protect the engagement points of a road pedal. These look promising, based on Favero statement: "Compatible cleats: Original LOOK Kéo and Favero cleats (red and black)."
Other option...have you considered just swapping pedals between rides? Keep a set of large platform flat pedals, like the Shimano PD-EF205, for your commutes, and put the power meter pedals on for the workouts. Regardless what you may read, pedals do not have to be torqued down tightly to prevent coming loose; they are threaded (L/R) so that pedaling forward continually keeps pressure on the threads and prevents them from "backing out." And the Favero pedals, and Garmin Vectors (3rd gen), don't require a specific torque when installing, just thread them onto the crank arm and snug them up, calibrate, and go.
Note, if you are going to be collecting power data on every ride, workouts and commutes, and on one type (the commutes) you are on "flat" pedals...DO NOT COMPARE THE DATA. It won't be applicable. Without a positive connection to the pedal, the power data will be different.