test.py

import tempfile
import os
import shutil
import glob
import bpy
import sys
 
addon_folder = 'io_import_scene_unreal_psa_psk_280'
 
source_path = '' #path to /blender3d_import_psk_psa here
 
files_mask = '*.py'
add_files_names = []
 
addon_path = os.path.join(source_path, addon_folder)
 
files = glob.glob(os.path.join(addon_path, files_mask)) + [os.path.join(addon_path, file) for file in add_files_names]
 
with tempfile.TemporaryDirectory() as temp_dir:
 
    addon_folder_to_files = os.path.join(temp_dir, addon_folder, addon_folder)
 
    os.makedirs(addon_folder_to_files)
 
    for file in files:
        shutil.copy(file, addon_folder_to_files)
 
    addon_folder_to_zip = os.path.join(temp_dir, addon_folder)
 
    shutil.make_archive(addon_folder_to_zip, 'zip', addon_folder_to_zip)
 
    addon_zip_path = addon_folder_to_zip + '.zip'
 
    bpy.ops.preferences.addon_disable(module = addon_folder)
    bpy.ops.preferences.addon_remove(module = addon_folder)
 
    for module in list(sys.modules.keys()):
        if hasattr(sys.modules[module], '__package__'):
            if(sys.modules[module].__package__ == addon_folder):
                del sys.modules[module]
 
    bpy.ops.preferences.addon_install(filepath = addon_zip_path, overwrite = True)
    bpy.ops.preferences.addon_enable(module = addon_folder)