Suppose there are two ranges
A2:A4 = A, B, C
B2:B5 = 1, 2, 3, 4
Cartesian product should give the result A1, A2, A3, A4, B1, B2, B3, B4, C1, C2, C3, C4
In Excel the formula would be
=DROP(REDUCE("",A2:A4, LAMBDA(a, b, VSTACK(a, b & B2:B5))),1)
In Power Query, the formula would be
= List.TransformMany(Table1[Column1], (x)=>Table2[Column2], (x, y)=> x & y)