Rolling 12 month total over multiple worksheets and multiple sum columns

This somewhat assumes that the same number of rows will be used on the 2020 sheet as were used on the 2019 sheet. The following formulas may be pasted onto the Summary sheet.
For cell A4: =SUM(SUMPRODUCT(('2019'!$C4:$C117>=EDATE(TODAY(),-12))*('2019'!$M4:$Z117)),SUMPRODUCT(('2020'!$C4:$C117>=EDATE(TODAY(),-12))*('2020'!$M4:$Z117)))
For cell B4: =SUM(SUMPRODUCT(('2019'!$C4:$C117>=EDATE(TODAY(),-6))*('2019'!$M4:$Z117)),SUMPRODUCT(('2020'!$C4:$C117>=EDATE(TODAY(),-6))*('2020'!$M4:$Z117)))
For cell C4: =SUM(SUMPRODUCT(('2019'!$C4:$C117>=EDATE(TODAY(),-3))*('2019'!$M4:$Z117)),SUMPRODUCT(('2020'!$C4:$C117>=EDATE(TODAY(),-3))*('2020'!$M4:$Z117)))
For cell D4: =SUM(SUMPRODUCT(('2019'!$C4:$C117>=EDATE(TODAY(),-1))*('2019'!$M4:$Z117)),SUMPRODUCT(('2020'!$C4:$C117>=EDATE(TODAY(),-1))*('2020'!$M4:$Z117)))
Let us know if you have any questions.