In a really edge case, a song might have official translation for both artist and song name which is different from the romanisation. I simply propose to add this in allowances (see bolded text):
This solves the headache and confusion of inconsistent metadata (for example this discussion), since the translations are official, but the romanisation isn't wrong either due to the song being popular on Japan first before reaching the rest of world.
What is the implication of this proposal? More consistent language on beatmap listing. Since in the listing both artist and song title uses same translation or romanisation, it will make the listing become more consistent. Mixing up translation and romanisation when both exist for both artist and song title will make the beatmap listing looks ugly and unprofessional.
・ If a Unicode song title or artist has an official translation or romanisation provided by the artist, it may be used in the respective romanised field. If both a translation and romanisation are available, either may be used. Both romanised fields should use the same preferred metadata choice between translation or romanisation.
This solves the headache and confusion of inconsistent metadata (for example this discussion), since the translations are official, but the romanisation isn't wrong either due to the song being popular on Japan first before reaching the rest of world.
What is the implication of this proposal? More consistent language on beatmap listing. Since in the listing both artist and song title uses same translation or romanisation, it will make the listing become more consistent. Mixing up translation and romanisation when both exist for both artist and song title will make the beatmap listing looks ugly and unprofessional.
Original proposal
The original proposal was to completely disallow romanisation/translation mixing. However it's not feasible as it will ultimately fall to the mapper's discretion and preferrence. It is now been edited to simply discourage such mixup.