You're welcome. I have pass it to RD department and hope the specification can change in the future.
Feedback Tracker Admin
I'm very sorry that it's a specification for now.There is a walkaround.Please pick sub-prop，open Timeline Transform track，right-click，choose Curve Editor > Convert to Curve Data，then set Rotate key.There is a UI bug for Rotation Order.You can pick other object，then pick sub-prop which convert to Curve Data，Rotation Order will enable.
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