One idea could be to have the Dragon Slayers from Fairy Tail cross over into a different magical realm. They could encounter new types of magic and creatures that they have to learn to deal with. For example, a realm where magic is based on music and they have to figure out how to use their dragon slayer magic in that environment.
A third idea could be a crossover with a world full of ancient gods. The Dragon Slayers would find themselves in a situation where they are seen as either threats or potential allies by these powerful beings. They would have to navigate the complex politics of the godly realm while also trying to figure out how their dragon slayer powers relate to the divine magic present in this new world.
The best chapter pointer here is Chapter 120, "Jiang Li Can Actually Do Acupuncture?!". It opens with Facing the sudden and somewhat strange request from Jiang Li, Director Sun... and closes on Drink this." Wen Jiaojiao looked at the half cup of thick substance:....
If you want the clearest chapter reference, go to Chapter 118. Early on, At 8 in the morning, several guests appeared on time next to the...; later, the chapter leans on Seeing the five individuals walking together in unison, Director Sun was....
If you want the clearest chapter reference, go to Chapter 113. Early on, The next day, Jiang Lili was up before dawn as usual.; later, the chapter leans on But this time was different; as she got dressed and opened her room door,....
If you want the clearest chapter reference, go to Chapter 126. Early on, Wen Jiaojiao initially wanted to cause trouble.; later, the chapter leans on But when her gaze swept around and landed on Jiang Li, who was standing at....
If you want the clearest chapter reference, go to Chapter 129. Early on, When they saw that the live chat was full of praise for Jiang Li, those...; later, the chapter leans on Had they been used as pawns by publicity accounts?!.
Look to Chapter 107 for the clearest answer. It begins with On the plane, when He Yun had taken off his mask and greeted her..., keeps building through She had also figured out his current predicament of being trapped by..., and lands on Although Su Yinwan's recent change in temperament had been.
Look to Chapter 93 for the clearest answer. It begins with Jiang Li looked back and saw several aunties linking arms, walking up the..., keeps building through The leader was indeed the aunt to whom she had read fortunes this morning., and lands on I did the same when I was young, and when my dad.
The best chapter pointer here is Chapter 140, "Did Jiang Li Finally Crash?". It opens with In the evening, the setting sun was like blood, dyeing the entire earth a... and closes on I was just joking, just joking." Seeing that Wen Jiaojiao had no intention....
Look to Chapter 165 for the clearest answer. It begins with How come everyone else got a solid six points, and he ended up with just..., keeps building through Director Sun spread his hands, "Our staff calculated the total score with..., and lands on Various explosive Weibos sprang up like.
Look to Chapter 135 for the clearest answer. It begins with The sun blazed down mercilessly, but thankfully, the path to the mountain..., keeps building through Zhao Lang was also very humorous, and even the usually stoic Jiang Li..., and lands on Are you healed from your injuries?" Zhao Lang.