Delta between two matrix

Alright, I'm gonna solve my own issue, but in case someone need the same thing, I put the resolution I found that work (might not be the best option of course).

I duplicate Table1 to get Table2.

I create 2 new table: one with Bracket, one with Category, both link to Table 1 & 2 (WIll be the rows and columns for Matrix 3).

I did the 2 matrix from Table 1 and Table 2 with their associated filters.

To get the difference:

DELTA=CALCULATE(SUM(Table1[QUANTITY],ALLSELECTED(Table1[YEAR],Table1[REGION],Table1[CLIENT]))-CALCULATE(SUM(Table2[QUANTITY],ALLSELECTED(Table2[YEAR],Table2[REGION],Table2[CLIENT]))

I put those value in Matrix 3 with Row = Table3[BRACKET] and Columns = Table4[CATEGORY]

And it worked..so far 🙂

Nicolas