I've created 3 heroes with 20 stats and modified powers. If you're interested in having any custom heroes made for you, you can find that information on my fiverr at https://www.fiverr.com/share/vbGdNr . Don't try to change these heroes in any way; otherwise, you'll bug their stats and your game might have issues. There is a visual bug with all of these heroes. Their stats are 20 in every stat but the stat menu doesn't show that.
How to install these heroes
1. Windows + S key to open the search bar
2. Type in %appdata% press enter
3. Find the "My Battle for Middle-earth(tm) II Files" folder
4. Find the Save folder; extract the PNE.zip to get the three .cah files
5. Copy and paste the 3 .cah files into your save folder. If you did everything correctly, you'll have the heroes in your list.
Issues: You may not have a Save folder, so all you need to do is create a custom hero in-game to create it. Then just follow steps 4 and 5.