I had an urgent Zoom meeting while traveling in Tokyo, so I used the Station Booth at JR Shinjuku Station (South Entrance). The available Booth has a green flashing light that indicates it is empty.
If no one is using it, you can choose a time at the entrance, pay with Suica or Pasmo, and get inside.
The fee is not too expensive at 275 yen (about $2) per 15 minutes.
If you register in advance on the web, you can find available booths at JR stations in Tokyo
Inside, there is enough space for a Zoom call and Wi-Fi is available.
Although it was an urgent online meeting, I was glad to be able to use this Station Booth on short notice and attend the meeting successfully.
If you urgently have to attend online MTG while traveling, I would definitely recommend it.