Split Keyboard with Transpose

Hellow all,

This is what I am trying to figure out regarding split keyboard and using a transpose function...

I have a split keyboard setup with Bass on my left hand and Piano on my right hand.

When I play, for example, in Ab, the keyboard split I use and have setup works great but if I transpose my keyboard say -3 half steps, the sound comes as the key of F. This is because F is -3 half steps below Ab...

The issue is my keyboard split that I have setup for the key of Ab also changes down -3 steps even though I am still physically playing in the Key of Ab. Now with this transpose, my bass and piano is playing -3 which is good but the split has also moved as well.

Is there a way to be able to play in Ab with the keyboard split that I have setup and also be able to transpose it WITHOUT the keyboard split moving when I transpose. I just want the sounds to go up and down based on my transpose key but without my split changing.

(I hope this makes sense guys, Its easier to show you all instead of trying to explain it via text lol)