First off, you should try skimming through some episodes of the show throughout the seasons, try finding moments where both of them are full of emotion in different situations, just to see how they talk, and act, but if you’re too lazy like me, reference their personalities on one situation, like ok if it’s a vampire x vampire trope then find a moment that you recognize where Mike could be sort of energetic in a daring way, or you could reference him off of Boris, and for Will, watch the second and fifth season, his emotions are a lot more powerful and angry per say. So yeah, I know it’s a lot but it can really help, and I always will help a fellow writer in need