Source is here.

Opus VIII will launch on March 22nd, 2019. Starter decks that accompany it will be FF7 and FF14. Really, really nice box art.

(Note: This article had originally stated that it would be an XV starter deck accompanying the set, however with clarification from Square Enix, it seems that the second starter deck is going to be FFXIV based. Opus VIII itself will contain FFXV cards.)

Further details below, screencapped via the miracle of Google Translate.

Looks like it contains new FF9 cards, too!