XMerge v1.4.0 is released on Github
If you are an Excel guru, you probably don't need XMerge. But if you have a bunch of .csv or tab-delimited data files that you want to merge into one .xlsx file, this tool may be exactly what you're looking for.
I do a lot of work in AutoCAD, and I do a lot of ATTOUT on large groups of blocks containing lots of attributes. ATTOUT dumps those attributes into tab-delimited .txt files. I can end up with forty or fifty such files to examine.
Getting all those files merged into a single .xlsx file might be easy in Excel, but what if you don't have Excel handy? What if the cloud is broken? Or - what if you don't trust Excel to do today what it did last time you used it . . . you know, before the update from Microsoft.
I trust Python. And I trust my code. So this tool meets my need.
Designate an output folder, point to the source files and let her rip.
If you want to specify what columns get pulled into the new output file, just list them in the supplied configuration spreadsheet using any spreadsheet editor.
There are more details and options explained in the help menu.
XMerge is written in Python, compiled into a Windows executable using Pyinstaller, and then Inno Setup Compiler 6.2.0 cooked it down into a single .exe installer. Available here on Github.