Add option to modify drag and/or add take profit to EA during visual backtest

I am looking for a way to backtest a semi-automated strategy. My semi-automated strategy open and close most orders mechanically (through the use of an EA), however from time to time i have to modify manually the take profit of certain open trades in order to close before or later the opened position.

My idea is to add a function to my ea that will give me the opportunity to drag up or down the take profit of certain orders during visual backtest.

the function must be easy to use, the take profit should be easily dragged in the chart up and down.

Be advised that my EA doesn't open all the orders with a take profit (sometimes the order take profit is blank)