So they dubbed it and never released it? Why is that?
The story is as it follows:
After the S DVD release flopped back in 2011, a Brazliian fanclub that exists since the late 90s and had ties with Toei backed the release of new content.
They actually paid (!!!) for a dub of the R movie. They scripted the dub and selected the voice cast. Moon, Mars, Jupiter, Tuxedo Mask, Luna and Artemis were voiced by the same actors who voiced them in the Classic dub. Mercury and Venus's VAs from the R-Stars dub were brought back, as well as Chibiusa's only voice actress to date.
However, even though Toei didn't have any expenses with the dub itself, they gave up on releasing the movie on home video in the last minute, afraid of low sales. They didn't even get the rights to the dub in the end.
The 90s movies are coming to Netflix Latin America the next month, and Brazilian Portuguese dubs are included. The S and SuperS movies probably got a dub using the cast from Eternal (which completely ignored the Classic dub cast, and therefore most of the actors involved in this unreleased dub), but we are yet to discover whether Toei tried to rescue this R movie dub with the fans or comissioned a new one.