Applying to jobs from Canada

Hey guys, I’ve been working as a software developer with <1 YOE and due to my partner wanting to move to Japan for graduate school, I’ve started looking at jobs in Japan (we would move around early Sept this year). I have Japanese citizenship, but my language skills are conversational at best. I see that a lot of job postings here say “resident only”. Is this because of visa issues? Since I already have a Japanese passport/citizenship, meaning I can bypass the visa issues, would applying to “resident only” jobs be productive or are there other considerations that I am overlooking?
Should I clearly state in my resume that I have citizenship and some level of Japanese?

Generally speaking, companies are saying “residents only” because of visa issues. That you don’t have them does mean companies are much more likely to consider you. I’d make this explicitly clear on your resume and cover letter.

Thanks for the response