Kirito and Sinon's outfit will be available in GE2RB while Julius' clothing for Kirito and Alisa's clothing for Asuna clothing will be available in SAO:LS. [1]
In the localized versions (English subs) of SAO: Lost song the DLC is pre installed and can be found in the cabinet where you change your armor under equipment. Select "GE Collab. Outfit" to get them.
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