There is a possibility to pass information to the Guest OS using OVF/OVA.
Functionality is called OVF Environment or VMware Guestinfo interface. I'm not sure if this really fits to your use-case and needs.
OVF Environment is a special section in OVF in ProductSection where you can specify Properties with custom key/value pairs.
Like this:
<ProductSection ovf:required="false">
<Property ovf:key="my-static-address" ovf:type="string" ovf:userConfigurable="true" ovf:value="10.10.10.10">
<Label>My static IP address</Label>
<Description>Message about my static IP address</Description>
</Property>
<Property ovf:key="foo" ovf:type="string" ovf:userConfigurable="true" ovf:value="bar">
<Description>foobar</Description>
</Property>
</ProductSection>.
If you will specify ovf:userConfigurable="true" then the user will have a free text field during deployment when he can specify the static IP address for example.
Then there are two ways to deliver that to VM itself. This is called transport. It could be VMware VM Tools or ISO image attached as a CDROM.
1) VM Tools transport
VMware tools or Open VMware tools should be installed in Guest OS.
You should specify in OVF:
<ovf:VirtualHardwareSection ovf:transport="com.vmware.guestInfo">
After deployment you can read Product Section via vmware-rpc:
vmware-rpctool "info-get guestinfo.ovfEnv" which will return you XML formatted Product Section. Then it is up to you to parse this XML, extract key/values and apply configuration (e.g. static IP).
2) ISO transport
You specify <VirtualHardwareSection ovf:transport="iso"> in OVF.
Cloud/Virt platform will then extract Product Section, put it to the ISO9660 image as file ovf-env.xml and attach to the first available IDE device as a CDROM.
Then you can mount this CDROM, read the file, parse the values and apply configuration.
If you don't want to parse values by yourself, you can consider cloud-init as an option inside the guest to apply configuration. There are plenty of modules to apply IP config, SSH keys or just write and execute files/commands.
http://cloudinit.readthedocs.io/en/latest/topics/datasources/ovf.html
You have mentioned CoreOS which supports VMware Guestinfo interface.
https://coreos.com/os/docs/latest/booting-on-vmware.html