After removing most of the "I think this file isn't used in the code" files, now arduino IDE can compile this. I only tested this on USB audio loop back, so if someone willing to test this on real guitar, send me DM, i'll send you the files if I...
I tried to train a model for it, with hidden_size of 16, it spent nearly all the processing power available...
this hidden_size is the maximum that I can get.