So, I know sometimes when RPGs release new editions they continue storylines from previous editions and "advance" the setting's canon timeline. But if I'm reading correctly, both 7th Sea have the same start year (1668). Has anything been said about whether adventures or plothooks from 1e will carry over? Or will everything be "replaced" and restarted by 2e?
This is a reboot not a sequel. While the nations are the same (with some extras thrown in) and a lot of the NPCs are coming back, it's going to be different than the previous version in multiple respects.
John Wick left the design team for 7th Sea after he completed work on the Avalon sourcebook in 1st Edition. This means a lot of what was present in 1st Edition is content that might not meet his approval, so expect some major changes to take place.