Lighting brings an atmosphere to a room that is often not taken into consideration. If your current sconces are very strong, you don't need a ceiling light, however, please post a picture so we can give you accurate information. Thank you.

Not necessary in a powder room. If you have a ceiling exhaust fan, you could replace it with one that also has a light component. I don’t use mine often, but it has its uses.

A picture would be helpful, but if it's an average, small powder room, sconces are probably enough light. When you're using the room does it seem like enough light to you?

Maybe? Maybe not?

I need pictures please posted here in a comment/

It totally depends on the room. Post pics and draw a little layout. Scone may be enough but we don't have enough info to go on.