Heroic Portraits?

They count
I remember getting 715 BP instead of 615 from 40AP quests with one servant and support with portraits so it works

as long as any servant in your team (doesn't have to be first 3) has the Heroic Portrait equipped, then your entire team will get +50 Bond Points after the battle. Keep in mind Heroic Portrait does stack, so you can take a friend's support servant that has it equipped as well to get a total of +100 bond points