The Ranking Criteria of metadata has been amended recently, https://osu.ppy.sh/help/wiki/Ranking_Criteria
"Songs with Japanese metadata must use the Modified Hepburn Romanisation method in romanised fields. The same applies to the Source field if a romanised Source is preferred by the mapper. As a non-unicode field, long vowels such as おう and うう should be romanised into ou and uu to avoid macrons."
For consistency of the romanisations in the future maps, we'd use modified hepburn ways over official romanisations.
"Songs with Japanese metadata must use the Modified Hepburn Romanisation method in romanised fields. The same applies to the Source field if a romanised Source is preferred by the mapper. As a non-unicode field, long vowels such as おう and うう should be romanised into ou and uu to avoid macrons."
For consistency of the romanisations in the future maps, we'd use modified hepburn ways over official romanisations.
