Yes.
The plant would grow as if in one larger combination of your two containers, so the plant could get proportionately larger.
Yes I grow outdoors whenever feasible.
This is my first grow of autoflowers now underway.
I have grown lots of photo plants in small containers outdoors.
But I never tried autos until this grow. The shorter plant is about 14 inches from soil line.
For your situation I would use no larger than about 2.5 liters, depending on how many times a day you can water/feed. Start/leave the plant in a tiny container until you know sex, then transplant into larger pot. Maybe use a low profile type container, better wind stability. The smaller the container the smaller the plant, so your plan to use the 11 liter would provide too big of a plant if you want to keep it real small.