Call py in scripting tab after opening blender

I currently use this bat to call blender and pass a fbx at runtime (via Send-To menu)

    @echo off
SET FBX_FILE=%1
SET BLENDER_PATH="C:\portableapps\blender36\blender.exe"

echo import sys > temp_script.py
echo import bpy >> temp_script.py
echo fbx_file = sys.argv[-1] >> temp_script.py
echo bpy.ops.import_scene.fbx(filepath=fbx_file) >> temp_script.py

%BLENDER_PATH% --python temp_script.py -- %FBX_FILE%
del temp_script.py

Now the thing is: I also want to pass a python script to the "SCRIPTING tab aswell after that.

neither the "-P" flag will achive this, not any other method.

Is there a way to have blender open say "C:\Blender\exportscript.py" into the scripting tab after this ?

So I can then just run it ?

#Note: I do not yet want to execute the py at runtime. just preload it, so it is sitting there waiting prettily in the Scripting tab.