While I had the frunk bin out doing some maintenance on my car recently... I noticed the placement of some components under there, A/C compressor being one of them.
It so happens this summer I had notice some very loud (embarrassingly so) A/C compressor noises coming from outside the car, that could also be heard inside the car, along with some vibrations..
I noticed a couple things that may have contributed to the noise, and made corrections (at zero cost) in effort to solve the noise issue. Maybe this will help you too?
For the record, my car is 2014 RWD with largest frunk ever made. The A/C compressor is mounted near the front of the car under the bin, and toward the driver side. (The brake vacuum pump is forward and to the passenger side). The compressor is mounted nicely on springy bouncy things that is meant to isolate vibrations. (So is the brake vac pump.) I do not have "the blanket" fix or whatever mod was made for noisy compressors.
1. An A/C hose to the compressor was bumping the bottom of the frunk bin! You could tell this because everything under the frunk is dusty from road dirt... but one spot on this hose was cleaned off from rubbing... So that would be whacking the bottom of the bin like hitting a drum and amplifying noise. The hose is a combo rubber tubing aluminum piping thing that can be bent down away from the bin slightly by bending the aluminium tubing part. No more contact.
2. The wiring connector / harness mating pair for the A/C compressor had fallen from its slide-on mount and was lying at the side of the compressor, now freed and being subject to vibration and rattles because it's a hard plastic thing hitting on metal parts that have a lot of movement. I saw how the connector should have been mounted and slid it back on with a positive "click" once firmly in place. I think it may have never been mounted correctly from factory assembly. It seems like it's going to stay on its mount now, so one less thing to buzz.
I'll need a real hot day next summer when A/C is operating at full thump to tell if these things made a difference to noise levels... but intuitively, pretty sure that hose was a major contributor.
Maybe check this on your car first if you're off warranty and getting loud A/C compressor sounds. It could save you a lot of money from blindly having the A/C compressor replaced.