If the seat tube angle is 1 degree different. You will have to move your saddle either foward or back to get the same set back from the center of the BB.
You may or may not need a setback seat post or zero set back post depending where the saddle is clamped on it's rails.
what will change is the front center. The steeper the seat tube angle, then the longer the front center will be. You have to consider the tube length and angles of any frame to see how it can be set up.
If 2 bikes have the same top tube length, then the one with the steeper seat tube angle (asuming the distance behind BB is equal) will need a shorter stem as the reach will be longer.