Is Alter Reality legal in Standard, Modern, and Commander?

Alter Reality is legal in: Legacy, Vintage, Commander.

Alter Reality

Q: What type of card is Alter Reality?

Alter Reality is an Instant. Its oracle text reads: "Change the text of target spell or permanent by replacing all instances of one color word with another. (This effect lasts indefinitely.) Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)"