Try that. AI easy would be rather pathetic.
I will presume you re playing a steam version on a modern computer running a Windows 64 bits.
classical installation path is C:\Program Files (x86)\Steam\steamapps\common\Company of Heroes Relaunch
Check for a specific file : tuning.rgd. usual path C:\Program Files (x86)\Steam\steamapps\common\Company of Heroes Relaunch\Eastern_Front\DataAttrib\attrib\tuning
Change its name in (for example) tuning.bak instead of tuning.rgd. unpack the tuning.rar and place the new tuning.rgd in thesame directory with the tuning.bak.
You ve now your new (very) easy AI.
Point you will be no more able to play multi.
Once your tests are over, rename the modified tuning.rgd in tuning.cheat (for exemple) and revert tuning.bak into tuning.rgd.
Your now with original Eastern front game.
if you need to test once more, just restart the process. tuning.rdg in tuning.bak, then tuning.cheat in tuning.rgd.
Let me now if it dont work or dont fulfil your goal