New 14" MacBook Pro M1 Pro - Finder keeps freezing when adding a tag color

Hi adweinbe,

For help with adding a tag color to files, have you tested with files not on the external drive? If not, test and see if using the steps for tagging with keyboard shortcuts seen below and found in the guide here will help: Use tags to organize files on Mac - Apple Support

"Tag files and folders

You can add multiple tags to any file or folder.

On your Mac, do any of the following:

• Tag an open file: Hold the pointer to the right of the document title, click the down arrow , click in the Tags field, then enter a new tag, or choose one from the list.
• Tag a new file when you save it: Click File > Save. In the Save dialog, click in the Tags field, then enter a new tag, or choose one from the list.
• Tag a file on the desktop or in the Finder: Select the item, then open the File menu. You can also Control-click the item, or tap it with two fingers. Choose a color  above Tags (the name of the tag replaces Tags as you move the pointer over the color), or click Tags to choose from more tags or to enter a new tag.
• In a Finder window, you can also select the item, click the Tags button , then enter a new tag, or choose one from the list.

Tip: Use keyboard shortcuts to tag files quickly—select a file, then use Control-1 through Control-7 to add (or remove) your favorite tags. Control-0 (zero) removes all tags from a file."

Additionally, you can test the steps here: If your Mac runs slowly - Apple Support

Best.