Sure, no problem.
Yes, I’m sure that if you have Avast installed on the host system, it’s not going to allow anything to “cross-over” to your machine without letting you know about it first. The network shield and on-access scanners will let you know of that pretty quickly.
Now we just need an avast developer to step in and tell us if there is a way or even a need to protect virtual interfaces created by VMWare. I’m going to bet that they don’t need it since the system will be protected by the various other shields, and they probably wouldn’t be able to create a driver for a virtual interface anyway. I don’t even know if VMWare releases the code for their virtual network connections, so it might be impossible for developers to create filter drivers for them.
Just my $.02 though.