I have used shavers on heavily feathered hens/roos (Silkies) Cover their face and hold them tight. It's a little scary for them but they will be fine they may steer clear of you for a few days but that's it...LOL
PLucked feathers begin to grow back immediately. Scissored feathers don`t grow back until they moult. If you do a decent job with scissors, there will be no problems. If the clippers work OK, check for stubble.........Pop
When clipping it is key to remember that the feather fluff directly under the main tail of the hens down to the vent must be trimmed to about 1/2 inch and the male needs trimmed the same way but from the vent down to the hocks to keep his fluff out of the way. I also trim the fluff from under the males tail as well since I'm already there. I have large cochins hatching like popcorn right now. I do not recommend plucking as this can cause the bird to bleed which could cause problems with the other birds picking and eventually killing the injured bird, plus it hurts like the dickens!!!!