Other languages have started to eat into Java's market share, but coincidentally a lot of them run on the same host VM as Java. For instance, Kotlin, Scala and Clojure are more and more frequently seen in backend, web and mobile development.
These languages are definitely much more "portable" depending on what your definition of portability is; the JRE runs on A LOT of systems and abstracts much of the underlying system away for you, meaning that IME you have to write a lot less platform-specific code if you're targeting e.g. Windows, macOS and Linux.
As for your edit, the licensing is a bit complex for Java but TL;DR if you install OpenJDK releases you do not need to worry yourself about licensing.
These languages are definitely much more "portable" depending on what your definition of portability is; the JRE runs on A LOT of systems and abstracts much of the underlying system away for you, meaning that IME you have to write a lot less platform-specific code if you're targeting e.g. Windows, macOS and Linux.
As for your edit, the licensing is a bit complex for Java but TL;DR if you install OpenJDK releases you do not need to worry yourself about licensing.