Mixing installations how to

I am just wondering if anybody knows how to put up category links on one installation on the front page of another.

I am running a website with multiple wordpress installs that are all linked together.

So I want to put up category links on my home page https://www.vagabondjourney.com from my other installations at https://www.vagabondjourney.com/travelogue and https://www.vagabondjourney.com/travelhelp.

Does anybody know if this is possible? Is there a plugin to do this?

Thanks,

Wade