Eu também deparei com um método para atribuir vários IPs estáticos e manter a funcionalidade do DHCP em uma única interface - link
não é exatamente o que você está procurando, mas pode ajudar.
Copypasta do site vinculado sugerido pelo comentário:
Setting the connection to obtain the DHCP provided IP
To setup the connection in order to automatically obtain the IP
address from the DHCP, you need to right click on the Local Area
Connection and to select Properties. Under the General tab go to
Internet protocol (TCP/IP) and select properties.
The options "Obtain IP address automatically" and "Obtain DNS server
addresses automatically" must be selected. Under the next tab,
"Alternate Configuration", "Automatic private IP address" must be also
selected. With these settings you ensure that your computer obtains
the IP address from the DHCP server.
Review imageReview imageReview imageAdding more static IP addresses
Next step consists in the operation of adding another static IP
addresses (not provided by the DHCP server). Because from Windows
there is no option to offer you the freedom to add more IP addresses
that can be used in the same time, we need to do a little trick
editing the registry.
Open the registry editor (Go to Start > Run and type Regedit) and look
for the following path:
HKEY_LOCAL_MACHINE>SYSTEM>CurrentControlSet>Services>Tcpip>Parameters>Interfaces
Here you will find a key look like this:
{BDF058FE-237C-402A-ABAB-8DEB342026BC}. It is the one that represents
the NIC card. You need to look for the one representing your own
network card.
Once you found it, select it and in the right panel, look for
IPAddress key. Double click on it and you will get the Edit
Multi-String window with a value of 0.0.0.0. Under this value, just
add your static IP. You can add one, two or more IP addresses
according to your needs.
In the same right panel, look for the SubnetMask key. This key needs
to be edited in the same way we did with the key above.
Now close the Registry editor and disable the network connection by
right clicking on the tray icon. Re-enable the connection again and
you are done.