Blizzard has clarified more or less when players will be able to play Orisa outside of Public Test Realm.
Director Jeff Kaplan stated that the team are still working on bug fixes and feedback for the versatile off-tank character.
Kaplan later gave a lengthier answer on the official forums. “Just to clarify, we’re leaving Orisa on the PTR for a little while. We’re getting great feedback and fixing a lot of issues.
“I know this feels a little longer than other PTR periods, but we think it will be for the better. We know how anxious you all are to have Orisa join your ranks…and she will soon…but most likely she will go live later in the month rather than this early.”
Personally, I would rather have a finished Orisa to get used to rather then have to deal with a buggy character that continuously needs buffs and nerfs in order to be evened out.