Long-term SMS rental for specific countries other than the US, EU and UK

Questions
1

When looking at services that offer long-term SMS number rentals and renewals, I often find that numbers for the country I live in are unavailable.

I am currently looking for numbers from Japan and South Korea, but most services primarily offer numbers from the US, UK, and EU.
Are there any SMS services that allow for the long-term rental and renewal of Japanese or South Korean numbers?

Services like SMSPool and SMSPVA offer Japanese and South Korean numbers for one-time verifications, but they do not seem to provide long-term rental options.

2

Does using one of the other countries phone numbers in Japan or South Korea cause services not to work?

3

In Japan and South Korea have Mandatory SIM-Card Registration, right ?

So if companies there respect the law, they will not sell anonymous SMS number I guess.

4

Yes. For some services in these countries, the content provided may differ depending on whether an overseas number or a local number is used.

5

Yes, SIM registration is required in these countries. However, since numbers are available for other countries with similar registration requirements, I suspect there might be a way to do it.