Unless your antenna(s) are very close or touching the carbon fiber it shouldn’t matter. I only have one fiberglass fuselage (a tank of a G-44 Widgeon flying boat) and in that I have a Futaba two-antenna diversity receiver. That one is doubly cursed with fiberglass and using 2.4gHz near the water surface. I am careful when placing any two-antenna receiver to make sure the antennas are at a true 90 degree angle to each other and as far from electric motors, batteries and ESCs as practical. Also as far from each other as I can arrange. To my knowledge in a lifetime of R/C I have never lost radio contact with a model.

That may well be because I am fussy about the receiver install and keeping the flight batteries well above cut-out.