spoiler pics - sheila & sugar (Spoilers)

I was trying to see if their hair was the same. Looks like same hair. Same outfit. they just had KB switch positions filming! You'd think Sugar would have dyed her hair or did something to look different! Oh, or maybe the point was to be identical so she could take sheila's life.

I do think the point was to be identical. That said Sugar was already identical when she went to prison for attacking Scotty and it seems like she wasn't out for long before she came after Sheila and got herself killed.

Did sugar take over the night of her stabbing?

It seems she abducted Sheila, and chained her up in the basement of an abandoned warehouse. Then went to kill Steffy. That's all we know. . Not sure what you mean by taking over.