I don't really got the time to do this right now, so I will try to avoid this solution for the moment.
However, I've removed VirtualBox and I have now no issue with the bluetooth, even after sleep during the night... Weird
I have still no sound if the sleep is too long (I don't know how long do I need to wait before it broke) but this is related to my CodecCommander configuration. Is it possible that the CodecCommander works for short but not long sleeps ?
Again, I can't really tell the exact difference between "long" and "short" (After a 1 hour sleep, it still works)
My CodecCommander was taken from this guide :
https://github.com/tluck/Lenovo-T460-Clover
I believe there is a mismatch between his OS version and mine
I maybe should try with AppleALC as suggested in his guide
Anyway this is a bit off-topic, I might reopen a post if I can't figure out the problem