Switch from run to bike, repeat

I sometimes move the bike share bikes and run between docks. I had the 735XT and was able to switch easily from run to bike while keeping it as one total exercise. 
I just got the Fenix6 and can’t see how you do this on the fly other than setting up a repeating duathlon session which I haven’t tried yet. I don’t know if you can do what I did on the 735xt. Sometimes I might start with a run but other times I might start with a bike so I’d rather be able to do it on the fly or would I just need to set up two favorites. One that starts with bike and the other that starts with a run?