A photo has been uploaded recently showing a flyer from the Consumer Electronics Show that Square advertised back in the day. It lists the following titles: FF I, FF Legend, FF IIj, FF Legend II, and there is a poster next to it showing a concept North American cover art for FF IIIj. I found it quite interesting that Square actually planned to release FF III for the nes overseas as well as FF II but you all know how that went (We did get them later though!).

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Flyer Shows Square Planned On Localizing Final Fantasy III For The NES Too | Siliconera