What's actually happening
When you copy rows from one file into another, you're doing what databases call a join. It matches records by a shared column (account number, job number, customer ID) and pulls across the details from the second file.
The reason it takes so long is that Excel does not do this automatically in the grid. Every row requires its own filter-and-read step. If either file changes shape, the whole process breaks and needs rebuilding. That could mean new columns, a different sort order or a renamed heading.
This is a normal problem with normal spreadsheets and there is a built-in fix that doesn't need formulas. It takes one careful setup, then two clicks a day.
The Power Query merge
Power Query is built into Excel 2016 and later on Windows, and Excel for Microsoft 365 on Mac and the web. It is not available in Excel 2016 or 2019 for Mac. It connects your two files and joins them on the shared column so you never open both files manually again.
Step 1: connect to File 1. Open Excel and look for Get Data under the Data tab, then From File, then From Excel Workbook. Menu names move between versions, so check your version if it looks different. Pick your account list (File 1). A preview opens. Select the sheet and click Transform Data.
Step 2: connect to File 2. In the Power Query Editor ribbon, click Home, then New Source, then File, then Excel Workbook. Pick your records file (File 2). Select the sheet and click OK.
Step 3: merge the two. With File 1's query open, click Home, then Merge Queries. In the dialog, pick File 2 from the dropdown. Click the shared column (Account Number) in File 1, then click the matching column in File 2. Leave the join type as Left Outer. This keeps every row from File 1, even when File 2 has no match. Click OK.
Step 4: expand the columns you need. A new column appears with an expand icon in the header. Click it. Tick the columns you want (description, date, category) and untick the rest. Click OK.
Step 5: close and load. Click Home, then Close and Load. Excel builds a sheet with the completed report. All the matching is done automatically.
Refreshing the next morning
Open the report file. Right-click anywhere in the output table. Click Refresh. The query re-reads both source files and regenerates the output. The daily work becomes two clicks.
When this will not work
Power Query reads files from a fixed path. Your shared network drive may use a different letter on each machine. The filenames may also include today's date. In either case, store the path in a named cell and reference it in the query settings. This is a single setup session with a bookkeeper or a support person who knows Excel.