Only the AP has an airforce/navy but it's incredibly weak. They have a large land army however. But numbers aren't everything. So the layout of the attack.
AAA troops are on the border and all of a sudden. Missiles, airstrikes, artillery barraging. It just happens. This is at midnight so no one was expecting it. The Anime forces invade into AAA territory but their advance is halted. The AAA manages to get fully mobilized and they push back the Anime forces. The Anime forces don't stop and they keep moving forward. But the AAA is powerful enough to hold them and push them back. This process repeats and the next day, crusaders receive word that the AAA is attacked. They immediately mobilize and they start sending troops to the AAA-Anime border. The Anime forces were already failing for a number of reasons.
1. the AGA doesn't have an air force or navy.
2. The main anime stream is neutral in all fights so they can't have the majority.
3. AGA is well lead but the AP is, well, they need more leaders who are active.
4. The AAA was already unstoppable but with the crusaders joining in they were definitely gonna lose. Their plan was to eliminate the AAA first before the crusaders join in. But if they succeeded, then IP, Pornpolice (maybe, not too sure), LoN, Thecoalitions, would all get involved.