Thats aircraft dependent if the flaps are on a common shaft which most are there is zero chance they are going to be asymmetry problems.
And one main gear not going down doesn't give much problems.
Most if not all heavy hardware have no restrictions deploying flap or gear in the turn. And its done many thousands of times per day.
If you already had a engine gone most will configure while wings level mainly to make life easier with trim and power changes but not because of asymmetry issues.