Who are they?

The blonde is Usagi as Princess Sailor Moon. She's from the Live Action o PGSM. The rosado, rosa haired one is a fan character, Princess Sailor chibi Moon.

sailor moon and sailor mini moon

The one on the right is Usagi (Sailor Moon) ,and
the one on the left is Chibi-Usa (Sailor chibi Moon)

On the left is sailor mini moon o Rini. On the right is sailor moon o Serena o Princess Serenity.

The blonde one is Serena / Sailor Moon and the pink-haired one is Rini / Sailor Mini Moon.