Vibration and noise on my 1997 V90

[AfonsoF1999]

For the past 2/3 years I've been having this noise and vibration coming from my car, and for the life of me I can't figure it out.

The vibration and noise are:

-seems to come from the engine bay
-worse when the car is cold.
-seems to match engine rpm, not necessarily speed.
-it vibrates quite intensely when starting up the car, then quiets down a little bit but never goes away.
-it sounds and feels like something is out of balance, almost like a out of balance driveshaft (and in fact it gets louder when the car is under g force, either turning or going over bumps).
-it's a dull sound, does not feel like rod knock as I expect it to have a more metallic sound.
-its been getting worse with time, but quite slowly.

In my quest to solve this I have replaced the following items, with no improvement to the problem:

-clutch and flywheel (and thrust bearing)
-engine mounts
-sparkplugs
-driveshaft support bearing.
-gearbox(the old one had a dead sincro ring).

I've also tried to look for exhaust leaks but couldn't find any.

I'm literally out of ideias of what it could be, any help would be appreciated.