Character development is a big part. The characters have to change their initial negative views of each other. In a good 'enemies to lovers' BL novel, you'll see how they gradually start to understand and care for one another. For instance, they might discover shared traumas or interests that bridge the gap between them.
You could also check out 'Given'. Ritsuka and Mafuyu have some initial friction. Ritsuka is a bit cold towards Mafuyu at the start. But through their shared love for music, they grow closer and develop a deep, loving relationship.
One great 'enemies to lovers' fantasy novel is 'A Court of Thorns and Roses' by Sarah J. Maas. It has a great build - up of the relationship between Feyre and Rhysand. Another is 'The Cruel Prince' by Holly Black. The dynamic between Jude and Cardan is full of tension and eventual love. Also, 'Shadow and Bone' by Leigh Bardugo has some elements of this trope as well.
Some excellent 'enemies to lovers' fictions are 'Cruel Prince' by Holly Black. Jude and Cardan are enemies in the faerie world. Jude is a mortal living among the faeries and Cardan is a cruel prince who bullies her. But over time, their relationship changes into something more passionate. 'The Cruel Prince' shows how power dynamics and initial hatred can transform into love. Also, in 'The Vampire Diaries' book series (although it has a TV adaptation too), Elena and Damon start off as enemies. Damon is a vampire who seems menacing to Elena at first, but as the story unfolds, they develop a deep and complex relationship that has elements of love despite their initial enmity.
One great enemies to lovers light novel is 'Red, White & Royal Blue'. It tells the story of a prince and the son of the US president who start off on the wrong foot but gradually fall in love. Another is 'The Hating Game', where two co - workers who constantly bicker realize they have deeper feelings for each other. 'Pride and Prejudice' can also be considered in a way, as Elizabeth and Mr. Darcy initially dislike each other due to pride and prejudice respectively, but then come to love one another.
In the movie 'The Princess Diaries 2: Royal Engagement', Mia and Nicholas start off as enemies. Mia is a bit clumsy and new to the royal world, and Nicholas is set on inheriting the throne. He sees Mia as an obstacle at first. But as they have to work together on various royal duties, they start to understand each other. Their little arguments and bickering turn into affectionate banter, and in the end, they fall in love.
Start by establishing a strong conflict between the characters that makes them seem incompatible. Then, introduce situations that force them to work together and gradually reveal their hidden vulnerabilities and commonalities.
Character growth is a key characteristic. The characters start off with negative views of each other. But as the story progresses, they learn to see past their differences. In 'Red, White & Royal Blue', the two main characters grow from being political rivals to lovers, and in the process, they become more understanding and empathetic.
'Aristotle and Dante Discover the Secrets of the Universe' can be considered in this category. Ari and Dante have a complex relationship at first. They don't understand each other but over time, they develop deep feelings for each other. It's a beautifully written novel about friendship evolving into love.
To write such a story, think about what could make them lose trust and respect for each other. It could be a life-changing event or a series of small incidents that accumulate over time. Also, show how their emotions change and how they struggle to deal with the transformation of their relationship.