TG blocks FA symbols when copied so you should not worry about your Posted symbols.

I have used all my XDAs from v17 back to v11 and all accept FA symbols directly into text.

A possible workaround - in Xara, if you change your Font to FontAwesome, you cannot input any symbols readily from the keyboard but it will work from the MS Windows Character Map application.
The downside is I only found a filled and an outlined star: U+F005 & U+F006, no half-outlined one.

Version 5 of FA (https://fontawesome.com/start) is quite a mouthful.

Acorn