I’d say that Trixie’s element would be Wonder.
|I always interpreted magic as “the force that binds us all together,” given that it’s supposed to be the central element.|
|I agree with The Smiling Pony’s idea, though with an addition of “Wonder” as OP mentioned.|
|Maybe something like “Inspiration”: her struggle to get back into the game, plus what she does for a living as a showmare and using magic to amaze.|
|Edit: Of course, on that note, that reminds me of the old headcanon that she could potentially be a replacement/understudy for the element of Magic itself.|
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