I have found using symbolic links works well. You can make a symbolic link of individual files or the folder you use to keep your MS files in. I put the the symbolic link in a Subfolder called symlinks in my vault and then you can link to the files in the folder as you would with a normal Obsidian note. When I click on the link in a note or on the file in the folder view they open in the appropriate application i.e. Excel, word, pdf expert, etc. If you symbolic the folder then if you add something outside of Obsidian it will update with the new file in Obsidian. These links also work on both my mac and windows machines as well as iPhone/iPad. You must use symbolic Links not Aliases. For reference my main Obsidian computer is a Mac which I sync with a Windows laptop and IOS devices.
You can use Terminal to create Symbolic Links or another program such as Commander One (Dual pane file manager FTP Client - Free version available) which has the option built in.