Is Autumn Equinox busy?

Ifll be visit Japan during Autumn Equinox (23 sept). Is this holiday busy?
Ifm planning to travel to Nagoya around that date, but I donft know if the attractions like Legoland will be busy or go the next day for less crowd.
If it is busy, maybe itfll be better to go shopping trip during the public holiday.

Whatfs your experience?

This year, it is part of a 3-day weekend, so you can expect popular tourist spots, such as theme parks to be much busier than usual.

Thank you Uji. Ifll make a note to do simple things like shopping with the kids.