Substitute text in a string if it matches a value in a table

I would like to look for a string in sheet 1 column A, compare to values to sheet 2 column A. If the value in sheet 2 column A matches any part of the text in sheet 1 column A, replace it with the value from sheet 2 column B.

Here is example data. I'm not sure how to write a formula to do this. Any thoughts?

Sheet1:
Column A
\\something\something,ABC\FJones,ReadAndExecute, Synchronize
\\something\something,ABC\RJones,ReadAndExecute, Synchronize
\\something\something,ABC\ASmith,ReadAndExecute, Synchronize

Sheet2:
Column A
ABC\FJONES
ABC\RJones
ABC\ASmith

Column B
XYZ\jonesfre
XYZ\jonesrob
XYZ\smithann

Expected result:
\\something\something,XYZ\jonesfre,ReadAndExecute, Synchronize
\\something\something,XYZ\jonesrob,ReadAndExecute, Synchronize
\\something\something,XYZ\smithann,ReadAndExecute, Synchronize

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=SUBSTITUTE(A2,Sheet2!A2,Sheet2!B2)

Ensure the Text matches exactly (upper/Lower case)

The formula works for the first two rows. Is there a way to do this by range without causing a spill to the next cell? I've modified the user value so that it matches exactly. Thanks!