Multiple VMs accross different segments in one VM box

Hi all. Noob question here.

My DC has a internet facing Tier 1 Firewall and internal facing Tier 2 firewall. Each Firewall are gateways to certain segments. As part of the DC transformation, lots of the servers are consolidated into VM boxes.

My worry is that VMs in one box are comimg out of 1 NIC card going to a segment where the Tier 1 firewall is the gateway amd another nic card which goes to the segment where the Tier 2 firewall is the gateway.

Is there any risk to putting tier 1 and tier 2 segments in 1 box? Are individual NIC cards like individual PCs in its own network that will never interfere in the box. Will VMs interact with each other in the same box?

Thank you reddit in advance.