Thank you for using EmEditor!
If this is the first time you try v10, it should import settings from v9, but of course, except new colors like Comparison-related and misspelled words. Then after you tried v10, and if you go back to v9 and change settings, those new settings will not be reflected to v10 because v10 uses a different entry for color settings. I hope this information helps.
Please let me know if you have further questions. Thank you!