Train your visitors well! (Meaning, only ask super compliant people to help you in setups!)
Leave a bag of small, bite-sized dog snacks outside your door and ask your visitors to grab a handful on the way in.
The visitor should come in and before the dog reaches them, they should immediately scatter the small handful of food on the ground at your dog's feet - now they are busy sniffing and foraging and NOT jumping!
If your dog knows how to sit, the visitor can reserve a few treats and ask for a sit as your dog finishes up the food-scatter.
Some training you can do in advance of a visitor is the following:
Look at That
The "Look at That" game is a really fun one to toss in here, especially if you have a VERY enthusiastic greeter. If you have not yet played the "Look at That" game with your dog, check it out here.
You can train this with your dog on leash and at a safe (can't jump on the visitor) distance, before allowing them to say hello!