How to disable the Character Viewer in Big Sur?
How should I change shortcut or disable emoji menu by ctrl+cmd+space. Is it possible?

Yes, it's possible, and you can change the default keyboard shortcut to something else in: System Preferences &gt; Keyboard &gt; Shortcuts &gt; App Shortcuts
Click the [+] button and in the sheet that appears...

Set Application: to: All Applications
Set Menu Title: to: Emoji &amp; Symbols

Use the actual menu title as it shows on the Edit menu on the menu bar, based on your Language &amp; Region settings. In this example it's English.


Set Keyboard Shortcut to e.g.: ⌃⇧⌘Space

After setting focus to it, press the keyboard shortcut you'd like to use. Once you've pressed the keys, click the Add button.



Note: Assigning global shortcuts can be problematic, and you'll need to use a keyboard shortcut that is not already assigned in whatever application has focus when pressing the new keyboard shortcut.