And the other soundtracks were recorded in London? That's pretty neat. I wonder if they were all at this same studio...
The full list of studios used for each film is as follows (taken from the OST booklets, and given in the order listed there, presumably greatest use first):
Jo: Abbey Road, London; Eastcote, London; Beethoven, Paris; King Sekiguchidai, Tokyo; Universoul 999, Tokyo.
Ha: Air-Lyndhurst, London; Abbey Road, London; Eastcote, London; Beethoven, Paris; Universoul, Form, Sony Nogizaka, Bunkamura, Ro-JAM up&downstairs, & King Sekiguchidai, Tokyo.
Q: Air-Lyndhurst, London; Abbey Road, London; Eastcote, London; Beethoven, Paris; National Philharmonic Hall, Warsaw; King Sekiguchidai, Tokyo.
In all cases only the London orchestra and choir are fully credited down to the individual players and singers, so they are clearly the main performers.
Actually although the NGE OST disks have much less info (at least in English), the very first of them has a picture of Abbey Road studio 2 being used to record Fly me to the Moon.