When comparing two logs, selecting a buff to see individually always shows the first character’s uptime regardless of which character’s buff is selected.
In this picture I selected Bestial Wrath and Bloodlust for both characters but it only shows my character’s uptime:
I tried manually changing the pins to a different target however I cannot change it to the 2nd player. I can select my character but every time I select the 2nd character (in this case Arouse) it blanks out.