It's a vital part of the fuel evaporation system. It has to periodically release the fuel vapors from the charcoal canister. I don't see how you could do without it.

What are the trouble codes you're getting?

I just went through a purge valve testing/replacement session, so I can help you out here.

 

There was a leak I fixed that and now it popped back up saying some EVAP purge valve system circuit, so I might just need to get a new one

 

What is the actual trouble code in Pxxxx format?

Common ones are in the P0440-P0449 range.
You can look up the description here. For example, a P0440 is
https://www.obd-codes.com/p0440

 

will a damaged purge valve affect Fuel Trims?

 

A bad purge valve alone should not affect fuel trims.

 

The purge valve is indeed part of the mandated EPA & Euro emissions system.
We work on a ton of E46's here, and have only replaced about 4 purge valves for an issue. More commonly is a vapor leak at/near the fuel pump/fuel tank lines for the vapor circuit.

Disconnecting the purge valve should set a CEL, in time. (DMTL faults likely?) Moreover when removed and/or disconnected you could have a couple of issues depending on where you live.
A removed valve and having the line vent to atmosphere can produce strong fuel vapors when the fuel in the tank experiences high temperatures. No fun to smell that stuff. Not to mention a small fire hazard.

Plugging the line will not let the fuel tank properly vent any built up pressure on those days where you have less than 1/2 tank of fuel and the temperature goes from 70°F to 95°F in the same day. Could compromise the tank and/or feed lines.

I've never tried it, but I also suspect that if the tank were near it's limit on pressure threshold, the fuel pressure being delivered to the injector rail would also increase. The regulator dumps the excess fuel back to the tank, but if the tank was .5BAR or higher over atmosphere, the resultant pressure would also be higher in the rail at some point?