If I grow it up to 4 weeks, I can get a clone,
spray it with colloidal silver to make it male.
We would like to cross these to obtain feminized female seeds.
Will this method be successful?
Timing with an auto would be a lot trickier than when dealing with photoperiods but it should work. It's the same technique used to create feminized seeds and to stabilize traits in strains with multiple phenos, you cross a female plant with itself to minimize/eliminate other genetic possibilities. Just a branch or two can produce enough pollin to fertilize a whole field of plants
Sorry bud but pretty sure you can’t clone an auto as It’ll just carry on its original timeline. I’m sure more experienced growers will correct me if I’m wrong but if you’re trying to clone you’ll need photoperiod genetics. Good luck. 👍