I like the layout. I have not played A&A 1940 (Europe, Pacific, or Global), but I imagine I would find this useful if I did. I do have a few suggestions though.
The background should be a bit more subdued. It’s coming through a bit strong and distracts from the information, making it harder to read. This is especially problematic for the smaller text near the bottom.
The decorative font you chose for the Political Situation and the charts is a good font for titles, but I would recommend using a more basic and readable font for the actual information. Your “Axis Victory | Allied Victory” chart is a perfect example of good font selection for title vs info with the title in an eye-catching font and the info in a more plainly readable serif font. This example should be followed throughout the reference sheet.
Keep up the good work. I’m sure the new players in your game will find this extremely helpful.