Mp3tag supports the creation and handling of a multi-value tag-field.
You should make sure, that your player supports the multi-value GENRE tag-field.
You can create a multi-value tag-field by a converter dialog or by an action or in the dialog "Extended tags..." manually.
Search for "multi value" in the forum posts.
Find out in the Mp3tag help manual what functions are provided to work with multi-value tag-fields.
Read there how to add one more genre ...
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