Found on Reddit;
Apparently, the Honda power unit matches the Mercedes power unit from the end of last season and is anywhere from 10-20 BHP down in race spec on the current Mercedes spec.
According to https://members.f1-life.net/report/80422/ (Japanese) Who is well known to have inside knowledge of Honda, the RA619H matches the Mercedes power unit from the end of last season.
https://www.auto-motor-und-sport.de/for ... lien-2019/
And according to this, Red Bull think they are between 10-20 BHP down on Mercedes in race spec right now.