Merz (CDU) is the new chancellor-elect, Scholz (SPD) was the previous chancellor (although really hed of a weak, unstable three-party "traffic-light" coalition). Weidel (AfD) also doubled voteshare to 20.8%. The SPD and also the Greens lost at last week's election, Habeck (Greens) quit, and they will both have less influence, and the Greens might not even be in the next coalition. Merz/CDU will be a main factor in the next coalition govt's position on Russia-Ukraine.
Clearly each of the above parties have differing views on Russia-Ukraine, just like Obama/Biden/Trump. That's how coalitions work. It's very different to the US two-party presidential system, where you can directly measure a leader's power by their majority in seats or voteshare.
I'm confused at what you're trying to say or how it relates to GP, but the very first statement is wrong, Merz isn't "chancellor-elect", that's not even a term anybody uses in Germany. He's merely the leader of the party that got the highest share of votes during the recent elections.
It is of course extremely likely that he'll become the next chancellor in a coalition with the SPD, but technically it could all still fail and lead to new elections. Unlikely, but not impossible.
Out of the parties you mentioned, mainly only CDU and SPD are relevant because it's the only realistic coalition (apart from decisions that require a 2/3 majority like reforming the debt brake). They're both pro-Ukraine although to different degrees (Scholz was dragging his feet quite a bit). Merz in particular has been rather vocal about this and as the chancellor he's probably going to be setting the tone. I don't like or trust the guy particularly, but I believe him in that respect. So I think the video got it essentially right.
Clearly each of the above parties have differing views on Russia-Ukraine, just like Obama/Biden/Trump. That's how coalitions work. It's very different to the US two-party presidential system, where you can directly measure a leader's power by their majority in seats or voteshare.