How to convert Max() KEEP (DENSE_RANK LAST ORDER BY) from Oracle to MariaDB or MySQL

Question

I'm migrate the Oracle to MariaDB. Got problem of convert the Oracle script to MariaDB script, this script can be convert to MariaDB?

This is a new server, running MariaDB 10.3.13. I've tried online convert (sqlLines) then paste code to HeidiQSQL execute and always got error.

SELECT o3.id,
    o3.FINISH_DATE,
    o3.START_DATE,
    o3.STEP_OWNER,
    o3.INITIAL_STATUS,
    o3.LAST_STATUS,
    o3.STEP_NAME,
    o3.STAGE_NAME,
    o3.REF_ID,
    o3.REF_STATUS,
    o3.ACTION_BY,
    o3.ELAPSED_TIME,
    DECODE (o3.STEP_NAME, '006' , 'Y' , 'N') AS IS_STP
  FROM os_historyrecord o3
  WHERE o3.id IN
    (SELECT MAX(prev.previous_id) KEEP (DENSE_RANK LAST
    ORDER BY o2.finish_date)
    FROM
      (SELECT id, stage_name, ref_id, finish_date FROM os_currentrecord
      UNION ALL
      SELECT id, stage_name, ref_id, finish_date FROM os_historyrecord
      ) o2,
      (SELECT op.id,
        op.previous_id,
        op.step_index
      FROM os_historyrecord_prev op
      WHERE op.previous_id IN
        (SELECT o.id
        FROM os_historyrecord o,
          LOSA_APP app
        WHERE o.REF_ID       = app.APP_NO
        AND o.stage_name     = '003'
        AND app.product_type = 'CL'
        GROUP BY o.id
        )
      AND op.step_index = 0
      ) prev
    WHERE PREV.id       = O2.id
    AND (O2.STAGE_NAME IN '004'
    OR O2.STAGE_NAME    = '005'
    OR O2.Stage_Name    = '006')
    GROUP BY O2.Ref_Id
    );

I expect the MariaDB out can be same as a Oracle.

Error prompt in HeidiSQL.