yes, we'd go back to physical scans. It's not like we won't be able to read weekly chapters translated by fans. But we won't have *official* translations. And also not official translations in 7 different languages if Shueisha wants to cancel the partnership.
In addition, this goes way beyond the weekly Chapters. It's about events and such that Shueisha and the one piece team started hosting together with Viz and other western companies. Like, literally the livestream on Monday where info got released simultaneously with the japanese fandom about the Movie, the Live Action, the Anime etc.
All of these things are in jeopardy.