From what I can find it’s okay. It’s not up there with the big shonen movies which are in the $10+ million range but, as an example, the slime movie got $1.4 million in its opening weekend.

Anecdotally, I saw it in IMAX and the theatre was mostly full, whereas I’ve only seen that for the Digimon 02 movie and Dragon Ball Super Hero in the past couple of years.