Wait till she's fully feathered. I'd assume seramas would be quite agile, though being frizzled might hender her escape a bit.
Do you have any other birds that are frizzle, similar size or patterned? Chickens can be super racist and they may just pick on her cause she's different too.
If the weather's in your favour, start integration early.
Weather permitting, I try to get my chicks outside for a short jaunt on the grass from 2 weeks old - (in a pen) and then free range the girls as an introduction of sorts - few sessions like this, then a day pen set up in the run - all day if they can handle it.
My current little babies just turned 4 weeks and have been outside for the past 4 days thanks to some wonderfully sunny weather. - they've abandoned the isolation pen to mingle with the big girls (unplanned, the little jailbreakers). There's 6 of them and 3 adult hens, so there's not much animosity. They have free run of the place and are enjoying themselves while being careful not to upset any of the big girls.
