New topic related to a recent one on whether international transfers within the same Japanese airport are allowed (they are!):

Does anyone know if Japan's COVID-19 regulations allow international transfers between two airports in the same Japanese city for non-Japanese citizens?

For example, arriving in HND and departing from NRT within reasonable time (or vice-versa)? Both flights are on ANA and on the same ticket.

I understand this means entering Japan proper (clearning immigration and customs), which at present is prohibited for most non-Japanese citizens.

But since ANA is inexplicably operating flights to different parts of the world from/to both NRT and HND now, some international connections are dicey. For instance, I want to get from YYZ to SIN, but ANA's Europe/Canada-Japan flights stop in HND, while Japan-Southeast Asia flights depart from NRT. US-Japan flights stop in NRT, but Canada-US flights are unpredictable, or else the connection times are terrible.

I'm tweeting ANA about this but it's like pulling teeth to get a clear answer.