To add to this list, here’s my experience from the Netherlands. It was much faster compared to some other countries.

23rd August: I sent the filled questionnaire to JTB
29th August: Received documents from JTB
5th September: submitted documents at the embassy in the Hague. No appointments needed, and a 3 person long line at the embassy. One of my documents was incorrect, was asked to email them the correct version.
6th September: emailed correct document to the embassy, received confirmation in an hour. Was asked to pick up my visa on the 12th.

Maybe for some of you, it could be easier/faster to travel to the Hague and apply from here, if you are allowed to do so. I’ve heard about people in Belgium having to wait a long time for an appointment at the Japanese Embassy in Brussels.