In theory this is possible, docker containers will run independent of each other. You’ll have to do some port management because all the instances will try to hook into the same ports on the host machine. This also means that requests have to be proxied on the host machine, you can use nginx for that (see example).
Also, the setup is going to need a server with a large amount of RAM, the minimum requirement is 4GB (for example, rasa-x installed on one of our servers uses about 2.5GB of memory when idle).