I'm guessing it wouldn't be preferred to use this as a stomp...
I read in the manual: By engaging the Rotary Speaker on an amp and cabinet sound that you like, you turn your cabinet into a rotary cabinet
It doesn't read anything about it in the manual but I'm guessing this effect is pretty important to use in the Effects section and not the Stomp section? Otherwise it would be sending a Leslie cabinet sound into the front of the amp which in the real world would be difficult but not impossible to do. Then the leslie sound would be affected by any effects after.