Ranking Criteria > Metadata > Allowances wrote:
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.
you can use either one, although the translation would be better as it's apparently better known:
Ranking Criteria > Metadata > Guidelines wrote:
If multiple metadata options are available, priority should be given to the option which is most easily recognisable and traceable back to the original song or source. Official romanisations and translations are preferred for romanised fields so long as they are easily found and commonly recognised.
however, if the song has been ranked/loved before, you should use the existing metadata in most cases:
Ranking Criteria > Metadata > Guidelines > Standardisation wrote:
If the same song exists in the Ranked or Loved sections already, the metadata should be followed unless it breaks other rules in the ranking criteria or the official sources state something completely different.
also, if you use the translation in the romanised title field, you should add the romanisation to tags (and vice versa):
Ranking Criteria > Metadata > Guidelines > Technical wrote:
Tags should be added for related artists, alternate names for the artist, title, or source, contractions in any part of the metadata with the apostrophe removed, and whatever else may aid a player in finding the beatmap.