I usually hate Omgaverse nowadays because the plot framework is overused and they never add anything innovative to the concept of secondary genders. This went beyond the stereotype and fixed persona for each secondary genders and actually gave a solid personality to the main characters. Even without their secondary gender or the omegaverse part, the story could still work.
Their personalities are not tied to their gender, no toxic leading male, the characters know themselves well and are responsible adults.
Romance, But Not Romantic