BELOW METHOD (sideload) for testing purpose only. if conflicted with the legal right of KODI, should delete immediately.
1. First of all, a DEV account should be available for your microsoft account, reference link as
How to Put Your Xbox Series X or S into Developer Mode (howtogeek.com)
2.
Partner Center (microsoft.com), + new product, create the brilliant name of your project and from 'Product identity', you can get the Package/Identity/Name, Package/Identity/Publisher, Package/Properties/PublisherDisplayName
3. Installed the MSIX packaging tool from MS store and installed the driver from the optional function of application in WINDOWS.
4. Opened msxi files via packaging tool, changing the Package/Identity/Name, Package/Identity/Publisher, Package/Properties/PublisherDisplayName as indicatation in Step No.2, (Application name same as your project name). Save.
5. Return to Application overview, completed all six items of Submission, like Pricing and availability, Properties etc. section requirement refers to official documents as
Create an app submission for your app - Windows apps | Microsoft Learn
Note:
AA. Pricing and availability, set the app to private and cost to free
BB. when filling 'Pricing and availability', create a group to add your own MS account for authorize yourself to download app via link.
CC. Store listings, completed by editing exported csv files
DD. any error needed to be corrected, red word would be indicated, corrected or completed as documents.
6. If all passed (Status GREEN), submit to store and waiting for MS certification. The certification step usually takes a few hours, but in some cases can take up to three business days.
7. Downloads the app via the link in 'Product identity' if app successful certificated by MS.
If private app created by KODI official, it could be under control to authorize the test member by adding the MS account when BB in item