For emulating Sub GHz signals you can use your phone ! Make sure to pair Flipper zero with your phone via bluetooth and set up widget in the Flipper app and on your phone.
I using it this way for my garage doors … Flipper can stay in my glovebox or backpack and I will trigger it with my phone …easy and also low key! keep in mind that bluetooth on your phone and Flipper has to be turned ON all the time and also there can be some connection issue depending on what FWversion or system you running !