Dear Sir,
If I highlighted several verses in NETP Bible, when I switch another Bible such as CUVT, KJV, KJVA and WEB, the highlighted verses was not highlighted in other Bibles.
Is it normal? If yes, will you improve it?

No, this will never be changed. The reason is that Mantis allows you to highlight down to the individual word. A word you highlight in the NIV, for instance, may not even exist in the KJV version of the Bible. Since there's no guaranteed compatibility, highlighting must remain specific to the version of the Bible where you made the highlights.