For Mac, I followed a combination of suggestions from @matangs (in another question) and @Samitha Chathuranga

• First find the location of mysql on your device: where is mysql
• Next head to the location in terminal, list your files ls, there should be a file called mysqldump
• Paste the location of mysqldump in workbench MySQLWorkbench->Settings->Adimnistration->Path to mysqldump Tool
• Restart Workbench and now the error should be gone

My workbench version: 8.0.38

Ref for matangs answer: https://stackoverflow.com/a/13550906/25760606