France WILL still fall.
Germany has 4 Infantry, 2 Artillery, 6 Tanks, and 4 Mechanized Infantry that can hit Paris.
4 Infantry, 2 Artillery, and 3 Tanks from Holland Belgium, 4 Mechanized Infantry from Western Germany, and 3 Tanks from Greater Southern Germany.
34 ATK with 16 Units versus 26 DEF with 12 Units.
Just means that some German Tanks might be taken as casualties.
You could also be a bit more assured and send the Tactical Bomber from Poland as well.
Any Maginot Line Rule should also include the French/Italian border IMO. This section was known as the Alpine Maginot line, and had many fortifications along with natural mountain range defenses. The French defenses on the Italian border held the Italians at bay until the the armistice was signed and Vichy was set up.
So IMO the 3 tanks from Southern Germany shouldn’t be able to attack France through Italy either. Those 3 tanks going through West Germany into France would also hit the Maginot line.
Maybe instead of saying German (axis) units can’t go through the Maginot Line, the rule should give any attacking ground units -1 for all rounds of battle that cross the Maginot line (West Germany/France, and Northern Italy/France or S France). That way those units could still invade, but wouldn’t be as effective because they are facing more resistance. Yes you would have some inf with no attack value, but could still be taken as a casualty. If that proves to harsh (which I think it might), then maybe have all attacking ground -1 only for the first round of battle when attacking through the Maginot lines.
So if the Germans were to back out after a couple rounds, the Italian units would also be -1 in attack when they go for Paris.
This could also be a good lead into a Vichy Rule