Index Match Array For Multiple Cells

How to do INDEX MATCH ARRAYS. (to populate my report I need to match multiple rows and columns from source sheet to import data).

Now I am trying to replicate same in VBA. (for this example row1&2 & column1&2 on both seed(source) and result(one I am trying to populate) sheets).

I wrote the code below that works just fine for 1 CELL.

Sub Button1_Click()
Range("C4").FormulaArray = "=INDEX('SEED'!$A$1:$f$6,MATCH(A4&B4,'SEED'!$A$1:$A$6&'SEED'!$B$1:$B$6,0),3)"
End Sub

I know in excel I can simply drag the formula across rows/columns to populate them automatically and the way I would do this in VBA would be by creating loops.

Here is what I have that needs improvement

Sub Button1_Click()
Dim iRow As Integer
For iRow = 3 To 4
Range("C" & iRow).FormulaArray = "=INDEX('SEED'!$A$1:$f$6,MATCH(AiRow & iRow,'SEED'!$A$1:$A$6&'SEED'!$B$1:$B$6,0),3)"
Next iRow
End Sub

Here iRow is to identify row number, and to keep simple I am only doing 2 rows. but how do i write MATCH statement to identify rows needed to be matched from SEED sheet?