Since an XAPK is fundamentally a ZIP file, you can "convert" it manually using any standard file manager. How to install an XAPK file - Uptodown Help Center
Additional code files optimized for specific device configurations. xapk to apk converter online free
If your XAPK contained an OBB file, the game will not work unless you move it to the correct folder. Since an XAPK is fundamentally a ZIP file,