Gaming Question about Japanese Virtual Console games

[Zowayix]

Are the differences between the NES SMB1 and the FDS SMB1 kept when downloading SMB1 onto the 3DS's Virtual Console on a Japanese 3DS and a non-Japanese one?
Does SMB3 from the 3DS's Virtual Console (currently Japan only) play like the Japanese SMB3 or the international one?

On the NES/FDS, there were various differences between the language versions, namely:
SMB1:
- Minus World is different
SMB3:
- Text; level transitions take 1.5 seconds longer in JP version; Fire/Raccoon/Suit Mario drops directly to Small Mario when damaged in JP version; a few levels like 1-Fortress and 8-Lava Ship are a little bit harder on the JP version

 

[loco365]

I'd presume that the respective country's game is used, so the original Japan SMB3 would be used in Japan, and the US version in the US. Perhaps look into that with the Wii's versions, because those changes will probably be reflected there as well, if any.

 

[RodrigoDavy]

Afaik, Super Mario Bros was released as a cartridge game in Japan and just happen to have a FDS version.

Anyway, I think it's more likely that the japanese VC version of SMB is the famicom cartridge version, since FDS games requires swapping the side of the disc and have longer loading times