Here is a better translation by Artur until Sandman comes out:
I don't see any language about "sacrifices", just some stuff about the meaning behind Luffy and the Strawhat's fights becoming clear. Also, no suggestion Wano will end in 2020 or else Oda would hype something like Luffy vs Kaido again or at least the epic final war that will eclipse Marineford.
The "meaning behind their fights" likely refers to the motivates behind the battle in Wano becoming clear. Up until now, "open the borders of Wano" was a just a very vague historical reference to isolationist Japan. What is the Kozuki family hiding? Were they protecting Wano and its ancient secrets from the risking the wrath of the World Government? Or is it more of a hold hands and Kumbaya thing with Wano joining the international order? Could be both.
I do expect the opening of Wano will for some reason shock and force the World Government to act in a way it hasn't done since the Void Century. Maybe I'm-sama is only targeting Vivi for now, but after Wano a global purge could begin as their worst kept secrets start coming out from Wano, Toki, etc.