Yes, you are correct. A magic number gets generated when we export a strategy as an EA.
Your results in FX Blue will match your results in the Validator. What you can do, is instead of using FX Blue, simply use the Validator to check the performance by changing the dates in Data Horizon, and adding acceptance criteria and performance filters. You can then remove the EAs / Strategies not performing, and export those that are as new EAs with new magic numbers, either as individual EAs or as a portfolio EA, and attach it it / them to your chart/s.
Hope this helps,