We can't determine much from your video, because it only shows one window. If you show us all windows, we can probably show you that they are all, in fact, jumping at the same time. Or, use one window, but a window that observes all of your characters without being one of them. (i.e. have your buddy record it for you from his toon). Your friend sees all of you moving at the same time, it's actually your main window that you see "wrong".
What you might be missing is the same thing Diablo 3 players are missing when they look at one window and move all of their characters together. "Hey, my main character moves before my other characters, they are OUT OF SYNC!" Well no, they're not out of sync, you're just observing the fact that it is a client-server game. (Here is one example thread from the Diablo 3 section, with this exact discussion, complete with a video just like yours:
https://isboxer.com/forum/viewtopic.php?p=11784#p11784 there are MANY MORE like it!)
The window you're looking at always moves the current character instantly based on your inputs. It does that because otherwise, it would feel laggy; when the game lets you move instantly based on your inputs, it feels nice and responsive.
All other windows have to wait for a message from the game server, to understand that the character that you're moving is actually moving. So your current character always appears to have zero latency. Your other characters, when observed from your current window, will move later because before you see them move, they send a message to the server, and the server sends a message back to your game window. This "delay" is directly related to your ping to the game server. If you have a 500ms ping, your other characters will appear to move about 500ms after your main character, from any window other than their own.
That's why you would want to look at all windows at once, or observe from someone else's account entirely. If you look at all windows at once, you can see each window with THAT character moving instantly, and the others all appear delayed. If you look at all of your characters from a different account, theyre all perfectly synchronized.
Hope that helps.