1997 V90 main crank bearings shot?!

[AfonsoF1999]

For the past 2/3 years I've been having this noise and vibration coming from my car, its been getting progressively worse as time passes by, and I think the the main bearings might be the culprit.

This is a recording of what it sounds like when acelarating, its recorded with the phone on the center console of the car. It does not seem to make the noise at idle or when coasting, and it seem to be proportional to how much power I request from the engine.

heres the recording:

What do you think? Is there anything else it could be? before I spend the money and replace crank bearings




TLDR
-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.