Convert VMX to OVA

vmx to ova conversion pretty much describes export of files between two virtual machine platforms, in this case from VMWare to Open Virtual Machine format. You can of course do that, but you will have to convert all the files that form the virtual machine, not just the configuration files. But if you have all the files, it should be a trivial matter to repack whole virtual machines so they can be used on different virtualization platforms.

Simply put, it is impossible to convert VMX to OVA directly.
Thus, there is no so-called vmx to ova converter or a free online .vmx to .ova converter to be found.