SOLVED:

Changed the power settings and set up a new power profile and made sure all of the settings when plugged in were the same as when on battery. Also reduced the max limit of the CPU to 90% for both.

So far so good. Have managed to play some demanding games with the charger plugged in and it hasn’t frozen since.

Still getting the same issue with the new charger

I’ve ordered a new charger so hopefully that resolves the issue.

I tried reducing the frequency of the gpu memory by 500mhz to account for the increase when the charger is plugged in but it still freezes