No. 2 picture: no issues.
Leather jacket, bootie and bag are in the same color group, match!
bright red sweater and black tights are good color contrast, match!
grey skirt with black and grey flower pattern goes well with the black tights, match!
The bright flowral scarf goes very well with the whole set. If the scarf color is darker than the bright red sweater, it won't go well.
No. 3 picture: try a color change.
I would make one change. Switching the brown leather pant to a black one. She is going to look like a female Zerro! Hahaha.
No. 4 picture: no issues!
I don't see any issues with colors. A yellow color sweater with some dark blue pattern. A navy blue skirt. Yellow goes very well with navy, plus a pair of white fashion sneaker.