Folks in Europe got the TV episodes on tape (en française), courtesy of Dynamic Visions in Belgium. There are three episodes in each volume, of which six were supposedly released as of July 2000. (I have been able to find little more about this series of videotapes; they have since disappeared from the Dynamic Visions catalog...)
Here are images of the covers for the cassettes, which featured other Classic DP artwork than was used on the original Japanese releases: the first is from a poster, with the image flipped; the second is from the Gakken Postcard Book; those for Volumes 3 and 4 were new renderings by Dokite Tsukasa; and the remainder may have been done by a local artist).
To resolve the mystery for those of us who have never this version, 'Dan' is the redhead and 'Danny' is the bluehead... This French-dubbed series first appeared on the FR3 channel in 1989; the voice artists were Dorothée Jemma (Dan) and Stéphanie Murat (Danny).
If you want to see a bit more about this series, visit MégAnimation: you can even run MPEGs of the traditional "Russian Roulette" episode opening (with French credits inserted) and the "Dan et Danny" promo clip. [Thanks to Aivars Liepa for bringing this to my attention. Note: this server can be very slow in responding.]
Wanna sing along? Here's the lyrics for "Dan et Danny"! [Words and music by Jean-Daniel Mercier, performed by Marie et Sandrine; the verses in green are omitted in the promo.]
Nous sommes deux filles inter-spatiales
Des détectives inter-sidérales
On nous appelle Dan et Danny
Les anges de la galaxieWe are two space girls,
Interstellar detectives.
They call us Dan and Danny,
The Angels of the Galaxy.Vient un danger, une menace
Nous surgissons des quatres coins de l'espaceWhen there's a danger or a threat,
We appear from the four corners of Space.Refrain:
Dan et Danny
Dan et Danny
Vous tous dans l'univers, attention nous voici
Dan et Danny
Dan et Danny
Laissez passer les anges de la galaxieRefrain:
Dan and Danny (Kei and Yuri)
Dan and Danny
Everyone in the Universe, here we are!
Dan and Danny
Dan and Danny
Make way for the Angels of the Galaxy!Nous connaissons la terre entière
Tous les p'tits secrets de l'univers
N'échappent pas à Dan et Danny
Les anges de la galaxieWe know the whole world,
All the lil' secrets of the Universe.
Nothing gets by Dan and Danny,
The Angels of the Galaxy.On vous provoque on vous menace
Nous surgissons des quatre coins de l'espaceIf you stir up trouble or are a threat,
We'll show up from the four corners of Space.Refrain (break musical) Dan et Danny ! [thanks to Psyber Raven for the translation to English]