AfD will not govern on national level in the next four years. I expect that CDU in some eastern state will eventually form a coalition with the AfD, but that has to happen first before they try on a national level. Then it will depend on the fall-out of that state coalition what will happen next.
But Germany doesn’t actually have a problem with illegal immigration. Almost all immigrants in Germany are here legally.
There are roughly 50.000 “Ausreisepflichtige” (Persons required to leave the country) out of a population of 84 Million. That number is roughly constant over the last 10 years. Doesn’t seem to be an issue worth discussing.
They are already in parliament and will gain votes but they will not govern, that’s pretty much guaranteed. We will get a conservative-led government though, a little to the right of Merkel. Most probably a conservative/social democratic coalition (think Mitt Romney Republicans with Biden Democrats) or a less likely less stable conservative/green coalition (think Mitt Romney Republicans with AOC Democrats).
The new government will be pro Ukraine (with the conservatives and greens extremely so, with the social-democrats a little hesitant but mainly, too) but also pro-Israel (with the greens more hesitant). All parties involved are pro European integration.
To be honest, foreign policies will not change much except for the European Chat Control legislation. While the current German government is strongly against it, Social Democrats are somewhere between indifferent and in favor, conservatives are strongly in favor and while Greens are against it, I can see them agreeing to a bad compromise with the conservatives.
That’s roughly a billion / a, nothing other countries couldn’t compensate if necessary. I’d rather have my country foot the bill than RFK Jr. having any influence on the WHO.