alt Hacker NewsGas/Hydrogen are Germany's answer to you last point.
You can store energy created by renewables this way easily and use it when needed. Right now we can't produce enough hydrogen though, so gas can be used in the meantime, but in the future the entire infrastructure, such as power plants, pipelines or port terminals can be switched to hydrogen: https://www.bundesnetzagentur.de/EN/Areas/Energy/HydrogenCor... You could even produce the hydrogen needed cheaply in countries with better conditions for solar and then ship it the same way we currently do with gas. Hydrogen power plants also have the advantage to quickly change output volumes, which is needed when most energy is produced by solar/wind.
Ideally German's investment into nuclear fusion pays off though as it would change the whole game. https://www.dw.com/en/nuclear-fusion-germany-bets-billions-o...
So they would use the excessive power generated by wind+solar into producing H2 from water and then transport it? Theoretically it can work, but as you mentioned, can they produce enough hydrogen to match the demand via wind+solar?
Nuclear fusion would absolutely be a game changer. But they it could take 5, 10 or even 50 more years to achieve that and by that time I don't know if German economy would be able to keep on pumping billions into research.