Quintet sure like making games with a re/building-the-world theme.
Japanese release dates.
Quintet are credited for 'item illustration CG', 'item graphics manager', and their logo appears in the 'in cooperated with' section, in the 2004 PS2 game Atelier Iris: Eternal Mana.
The Wikipedia page on Quintet suggests that they have made the same contribution to other games in the series (or perhaps the graphics are just reused, I don't know) but I can't find any credit videos to verify.
Quintet are featured in the credits of the 1987 game Dragon Slayer IV: Drasle Family, released in the west as Legacy of the Wizard. The western version doesn't include their name, but in the MSX version it can be found under 'Dragon slayer famiry', and in the Famicom version under 'Dragon Slayer 4'.
The Granstream Saga is often linked to the 'heaven and earth'(Soul Blazer-Illusion of Gaia-Terranigma) trilogy, though it was made by Shade, who contain many Quintet ex-employees. See link for credit analysis. Curiously it is listed on Quintet's extinct homepage in the 'Quintet Game Library' section.
Quintet receive a credit ('The Producers wish to thank the following' section; 'Production' subsection) in Shenmue, as do other game developers like ASCII, Ancient, Arc System Works, and SIMS.