Always check your license guide for up-to-date information on your specific database version, but at the time of writing, no additional licenses are needed to use SQL Plan Management (SPM) or any of the procedures in the DBMS_SPM package. SPM is available as part of Oracle Database Enterprise Edition. In addition, a subset of SPM functionality is available in Oracle Database Standard Edition from Oracle Database 18c onwards.
If you have a licence to use AWR and you are making used of this feature, then SQL plan management will make use of it too without further license requirements.
SQL plan management can use SQL tuning sets too. SQL tuning sets are available for use in Oracle Enterprise Edition and can be used by SPM without further license requirements.