gdal issue in QGIS3.4.14:"No module named gdal_merge" in Win10

[masterpigis]

Describe the bug
the existing solution of the former similar issue (https://trac.osgeo.org/osgeo4w/ticket/588) sofar is not applicable for this case, also all the other possible solutions were tried out but didnt work, including:
-numpy reinstalled and the latestes update
-environmental variable checked and reset

would appreciate for the help!

How to Reproduce

QGIS and OS versions

Additional context

[agiudiceandrea]

It seems similar to #33386

@masterpigis please see [1], [2] and #33520 (comment)

You could tray to workaround the bug, setting the PYTHONPATH environmental variable (in QGIS, Settings->Options->System) to the path of the folder in which there are the gdal_merge.py, gdal_poligonize.py, and the other gdal_*.py python scripts files: in the Environment box add a new row, with the value Overwrite (or Prepend) in the "Apply" column, the value PYTHONPATH in the "Variable" column and the path to the folder in which there are the gdal_*.py files in the "Value" column, then press OK button and restart QGIS.

[gioman]

Closed as duplicate.