Mysterium Network does not support multiple devices under a single IP address. Having multiple nodes will likely to affect your internet connection quality as well as reduce service stability thus making a negative impact on the network itself.
Each node must be linked to a different IP address, so unless you have multiple routers, each with their own IP and node linked to it, it's not possible.
Node operators running multiple nodes under the same IP address won't be able to propagate their service proposals (only one proposal per IP will be accepted into network. All subsequent proposal originated from the same IP will be ignored and displayed as offline on mystnodes.com).