The name for Red Square has both changed and also remained the same. This is because the name in terms of how it sounds stayed the same (krasnaya ploshad), but over time the meaning of krasnaya shifted from meaning beautiful to meaning red. When it was first called krasnaya ploshad it meant Beautiful Square, but now it no longer means that.
Bonus fact: this also means that Russian is basically the only language that uses a form of krasnaya to mean red. Most languages will have different ways to say red from the similar language families (red, rojo, rot, and rood are all related ways to say red from one language family), but not Russian. There will be other languages that use a form of krasnaya to mean beautiful, but not to mean red