That’s also part of the reason I’ve chosen it for a placeholder / variable name! The actual placing is not important as long as it’s where speakers of the Ä language expect to find it.
Or suppose there’s languages Ä₁ and Ä₂, where in Ä₁ the ‘ä’ is the umlauted ‘a’ and in Ä₂ it’s a distinct letter. The language list would be displayed as:
A Ä₁ B C Z Ä₂
The only problem / corner case would be such a language Ä₀ that would e.g. sort ‘ä’ before ‘a’. I would still put it after, since it’s where most other readers would expect to find it.
Coincidentally, the expected position of "Ä" can vary wildly. Is it an umlauted A, normalized as AE, or a distinct letter coming after Z?