If your question is concerning only the ''international'' nature of the journal, then I think by checking the editorial board of the journal you can notice if the editors and reviewers are from institutions based in different countries and that makes the journal an international journal.
I wonder what you mean really. International is supposed to refer to location and has nothing to do with impact or quality. Like Difo Voukang Harouna said, check the editorial board, if that is what you want. But if it is quality, confirm if journal is listed in Master Journal List, that's all.
Please do search regarding the journal in https://www.scimagojr.com site. Please see the impact factor, eigen factor, cite score which are the parameters to comment on the journal's reputation.
For a journal to be international, it should be indexed in ISI, Web of Science and Scopus (Q1, Q2) usually this kind of journal has a an impact factor that reveals its quality.