Is my irrelevant field of work experience a negative when applying for higher studies?
If you are applying to schools in Germany, your work experience is largely irrelevant whether or not it is in the discipline you want to study at the master's level. This is because the prerequisites for master's study at German universities is generally an equivalent bachelor's degree at the undergraduate level. However, if your bachelor's degree was not completed at a German university, you will have to petition to have your degree recognized as "equivalent" before being allowed to enroll.

There are some exceptions for "international" programs and special master's programs that do not require a specific degree program but their requirements and procedures must be investigated on a case-by-case basis.