weight 0.7 is best.
I created this LoRA as requested.

Please read the description.

outfit1 ( bob cut ↔ short twintails, parted bangs )
aarinko, short hair, black hair, bob cut, serafuku, sailor collar, blue neckerchief, white shirt, short sleeves, pleated skirt, blue skirt


outfit2 ( bob cut ↔ short twintails, parted bangs )
aarinko, short hair, black hair, bob cut, serafuku, blue shirt, long sleeves, sailor collar, white neckerchief, pleated skirt, blue skirt

other hairstyle
aarinko, short hair, black hair, short twintails, parted bangs

I uploaded a sample image of the outfit as a post.