Secondment experience needs to be written on work experience. This can be written. This is a work experience, the time is more than 2 months.
Write if it's useful, and don't write if it's useless. It has nothing to do with secondment. Many people or people around them have had secondment experience. As a special employment mechanism at present, secondment has different views. There are also many people who are hesitant to go, stay or transfer when facing secondment, and don't know how to choose.