You can do most autos outside - depending on whether they're partially automatic or fully automatic, you don't want to start them inside while it's cold and then move them outside as the weather warms up.

This can trigger partials to start blooming too early.

I believe that Short Stuff's are all fully autoflowering, so you should be OK.

If you're going to propogate your own seeds and plant outdoors, I wouldn't worry too much about feminizing them - especially if this is for your own use. It would be a lot of effort for a very little payoff - in my personal opinion.

You'd be better off keeping a mother plant inside and learning how to clone - or learning how to get your plants to give you a second or third harvest. To be honest, I'm not sure how either of those work with autos - maybe someone else here has tried it.