Hi @alisonmeininger
You need 2 flows to meet your need.
The first flow is ,as you implemented, to save each of the emailed Excel files to your OneDrive folder.
The second flow is to append emailed Excel data into the 4 corresponding sheets of another pre-existing Excel file.
And to match the emailed Excel data with the columns in another pre-existing Excel file, there is an easier way to check whether they are matched---just ensure the table names are the same.
You can edit table name by selecting the table, choosing ‘Table Design’ and then editing the table name:

I’ve create the second flow as below:
First, if a file is created in a specific folder in OneDrive, get file metadata and check if the file is an excel file.
If yes, get tables in the excel file and add an ‘apply to each’ action.
If no, do nothing.

For the ‘apply to each’ action:

Add a ‘switch’ action:
The switch action is used to find matched case. And if there is a matched case, then append the emailed excel data into pre-existing excel file.
There are four cases and an default one.

For each case in ‘switch’ action:




Best Regards,
Community Support Team _ Kira Xie
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