I don't understand why you need a battery power winder. I have too many battery things in my house as it is.
I find the manual one works fine and also doubles as a bridge pin puller and string cutter.
I find a bed with a soft comforter is a perfect place to change strings. I do need to get a headstock supporter.
Justin Guitar has a good video on change strings.
https://www.justinguitar.com/guitar-...-guitar-gm-105
Changing classical strings is a bear compared to a steel string guitar.