I love your idea here. A lot. Thank you so much for taking time drawing different characters! Seeing Bernadetta, Dorthea, Petra, the professor herself, and Edelgard in your own art style is very cool to me!

I like them in your own style.
Colds are your thing and I think that you did great with the way a cold can spread to others, especially close friends that have to be next to each other to get bonuses on the battlefield

seriously, especially on hard mode, standing next to allies is almost necessary. The bonuses can be a huge help.
A detail I notice here is the top panel. I love how you drew Byleth's hairstyle

but it is more than that I notice. The detailed sneeze face you draw are different than the lip sneeze expressions, and I love the detailed sneeze face expressions you draw, not just in this comic but in general!

the mouth and nose are clearly seen, and she definitely needs what you are offering Edelgard. Hankie, tissue, give the poor young lady something to help her out! XD
Speaking of Edelgard, the eyes. Both her chibi eyes and the colored eyes. The eyes made me smile when I saw them, and you did great with their unique color! Edelgard is poised, confident, good looking, and the conversation she did here I could honestly very easily see happening in the game if a cold spread like this.
.........how far into the game are you? I have a story I am planning on writing I want to share but it contains heavy spoilers about the church and Edelgard herself that is not revealed in any trailer.