Is there a formula in google sheets which fixes once a value is added?

I'm trying to see if there is a way to add a formula to a google sheets which will then fix the contents once a cell is populated.

Google Sheet Example

In this example, each week I replace the contents of sheet Changes Weekly, I would like any matches to populate into the Final Result sheet. I know I could do this with index match formula and just appending the new results to the bottom of the sheet each week but the data would build up quickly so just seeing if this alternative is possible. The data for the Changes Weekly tab also comes from another sheet so if this is possible I can just make this an import range and save some more time.

Thanks in advance,Riley