@SarahGen-- I wouldn't say that there are a lot of options, but there are several. Vegan cheese is usually made from tofu (soybeans), or nuts like cashews or almonds. So you should probably have both kinds in the platter. They are available commercially, but it's also possible to make them at home if you're interested. Nut cheeses are generally easier to make than tofu cheese.
If I were you, I would also include some veggies and fruits, olives and perhaps some hummus aside from vegan crackers. It won't be a classic type of platter, but you will have plenty of choices for your vegan guests.