Beating two AI on Arabia without rushing is extremely rough. Not rushing is practically giving away the most abusable factor of the map to your enemies for free. It’s like playing gold rush and not playing for the gold.
If you want to win on a map without rushing, you should play a map that is less open and easier to wall up (or starts with walls) and definitely not Arabia. Winning against multiple AI is already pretty tricky but trying to do it without rushing is moreso difficult.
That being said, beating multiple opponents at once is all about pop efficiency. They outnumber you heavily, so you need to make sure you’re investing into units that have high returns and are extremely population efficient whilst also hoping your opponents invest into a lot of low-value, low-cost units that you can capitalize against. So it’s going to come down heavily on civ matchup. Trying to win against something like Portuguese + Burmese or Indians + Koreans is going to be downright impossible if you don’t rush simply because their units are too pop efficient and they’ll have both a population limit advantage and a population value advantage.
The three things you need to do to win against multiple AI:
1. Identify your greatest lategame threat immediately
If you’re going Archer mass as your method of victory, you need to find and hit the Celt/Korean/Mongol. You can’t let that absurdly efficient, anti-archer army to get going. Going Cav? Hit the Viking / Japanese / Italian. They need to be first on the chopping block.
2. Use your age up advantage to control map and pressure opponents immediately
You will want to hit the next age running. Don’t let them recover if they spent all their resources on military. Pump out a few knights, kill that archer ball, and raid woodlines. Once you hit imp, get those upgrades and march. Once both players are in Imp you’re in deep trouble.
3. Spend your resources on powerful, efficient sources of military
Don’t make trash. Trash doesn’t push. You need to make a more population efficient army than your opponents if you want to win since they outnumber you. There are plenty of units that will hold value better and still work against the unit you are trying to counter, even for the Teutons. ETK’s vs Cavalry and infantry. Siege (in general) against Archers. Paladins against siege. If you’re making something else, you’ve probably messed up. That goes for any civ.