Can I ignore specific folder from being scanned?

Yes, you can set it to be excluded using a regular expression (regex).

  1. Go to Settings > Library > Exclusions.
  2. Click on Excluded Video Patterns or Excluded Image/Gallery Patterns depending on the type of content you want to exclude.
  3. Click Edit.
  4. Enter a valid regex and click Confirm.

[!tip]
There is a useful site regex101 that can help you experiment and test with regex.

See Stash in-app documentation for some examples: