I think I am making this more difficult than necessary ....

I want to do SUMPRODUCT where at least one array must
be composed of a "range" of non-contiguous cells -- namely,
one cell from each of N worksheets.

Ostensibly, I want
SUMPRODUCT(A1:Z1,ARRAY(Sheet1!A1,...,Sheet26!A1))

There is an ARRAY() function in VBA. But I do not find
any excel built-in function with the same capability. Did
I overlook it?

I created my own VBA function, myarray(). I also created
mytranspose() to handle the case when the first
SUMPRODUCT range is a column (A1:A26), not a row. It
obviates the need to enter SUMPRODUCT() as array formula.

These VBA functions are trivial to write. I cannot believe
"Bill's kids" cannot figure out how to do them as built-ins.
So I believe I "must be" overlooking the obvious.

Please help me. What simpler alternatives exist?