I noticed a roll to the left while cruising on the F-5 ACM campaign, but put it down to the instrumentation pod on the left wing-tip with the right empty.
The fuel load is not symmetrical, but from memory, the left tank has less than the right (dials rather blurry in VR), so I would guess it should go the other way.
Also, if you look at the rear of the plane sometimes, one engine is on AB, while the other isn't despite both appearing to be at the same throttle setting.
Lots of things could be effecting it ... sorry, not a lot of help!