1995 Acura Integra Automatic Transmission Issue (Main Shaft Bearing Issue?)

I’ve got a 1995 Integra with what I suspect to be a bad main shaft bearing issue. Overall, the transmission shifts a little rough at times. It accelerates pretty slow and it downshifts horribly. Aside from the shifting, every time I put it in reverse, I can hear a rough noise of rotation coming from the transmission. Depending on the temperature, it reverberates throughout the car as well. Can anybody confirm that it’s a bad main shaft bearing with that information? Or is it something else? Thanks!