Issue can also have two meanings - 1. A dispute or difficulty , or 2. A topic.
For definition 1 of issues, the difference between that use of issues and problems is that problems are usually difficult circumstances that require resolving. Issues are often describing the personal disputes or encounters a person experiences.
I'm not sure which context you're using the sentence you provided.
"There are different opinions on the issue of learning foreign languages" This sentence is already correct if you're using the word "issue" to describe it's meaning "topic." If that is what you are trying to communicate you could say "There are different opinions on the topic of learning foreign languages."
However, if the sentence you provided is describing the difficulty of learning foreign language, you would want to say: "There are different opinions regarding the problems of learning foreign languages." In this case you're describing the difficulty of learning foreign languages, and "issues" would sound too personal, problems would sound better. Since you're declaring a fact, using the word "problems" would sound more objective and sounds better in this case.
I hope that makes sense!