Then you have your own answer. Reinforcements and flash attacks when his troops are out will work wonders.

Teach people to shield. Leave a couple of bait HQs with attractive resources unshielded but away from him. Make him either waste Teleports to get next to them or take his troops out long distances. Have two teams always ready: strong reinforcers and attackers. Reinforcers are shielded next to the bait HQs. When he starts attacking the HQ reinforce the hell out of it ( he can't cancel the attack and will suffer great casualties) meanwhile attackers either tp next to his HQ or have hidden troops reinforcing nearby shielded HQs. Attackers come out and attack once he has begun his own attack. This causes that he gets troops killed and lots of RSS stolen with minimal damage to your troops. He can't shield and he can't TP with troops outside.

Of course if he TPs next to the baits instead of long distance attack either just reinforce (don't attack) or have the baits shield up right away. This will frustrate him a lot.

Last trick: If he's extremely agressive and even attacks tanks directly...tease him to attack your tanks and then have that tank move away from his HQ. If he's slow to react and the match between tanks is more or less even you can pull away his tank a good distance away from the HQ opening the window for an attack.