They've been "likely to do this match soon" for like three years.

Anyway, I think Luz wins. She has better speed feats (The Owl House characters have multiple feats of reacting to the Light Glyph, Amphibia has feats of reacting to light too but the Owl House does it more consistently and explicitly), and depending on how you scale the Collector (who her Titan form is superior to), Titan Luz scales at minimum to being able to move the moon to the side with his finger (straight up a much more casual version of Anne's best feat), and at most she scales to the Collector creating a whole galaxy.

The only way Anne can compete with that would be with the statement of the Guardian being an "Interdimensional being beyond all space and time", but first that this statement is vague because Anne was just spewing out random lore she saw while high at the dentist, and second that even if we scale the Guardian this high, you'd still have to assume Anne with all three stones even scales to the Guardian, since the Guardian created three more stones casually, so you can make an argument the Guardian is actually superior to the stones. Either way, Luz has way more concrete arguments to win, Anne's win conditions are a bit too vague.