Upvote:4
The specifics will depend on the countries involved but in most cases this is a really BAD idea.
Here is what probably going to happen
- You leave countryA with passportA and nameA pretending to go to C
- You have a transit in countryB. You abandon your flight and enter countryB with passportB using nameB.
- The airline will cancel the remainder of your ticket including your return flight (if there is any)
- If you have any luggage that's checked through to country C you will loose this too
- The airline will report to countryB that nameA did not board and has therefore illegally entered countryB. At this point you (under nameA) have committed a serious crime and are wanted as a an illegal immigrant in countryB
- The airline may report this back to countryA as well. Now you are potentially a criminal or at least "subject of interest" in countryA as well.
Stating the obvious: For most countries these would constitute serious legal offenses and can get you into serious trouble. Don't break the law. If you need to travel between country A and B then you need to abandon one of your citizenships.