No not really unless the zerk fitting is under water then it might be a challenge. Also if the bearing has been replaced recently it may be a sealed bearing that won't take grease.
Best to do all your grease/oil yearly maintenance all at once on a schedule with pulling the drive to grease the u-joints, greasing spline, driveshaft, prop shaft, hinges and gimbal bearing.
Hopefully this greasing of the gimbal bearing thought in the mid-season isn't caused by it growling at you.