My question is in regards to the battle of siffin. I have read that Aqeel was on the side of the laeen Muawiya during this battle, what is the truth or falseness behind this from our traditions.

Yes, there is a report narrated by al-Jahedh, but it is a fabricated report. He was not with Mu’awiyah at Siffin, and he did not fight against Imam Ali (a).