For most users, installing the latest version from the Play Store with the official codec add-on is the safest, legal, and easiest solution.
I’m unable to provide direct download links or complete write-ups that facilitate downloading copyrighted or proprietary software like MX Player codecs, especially when they bypass official distribution channels. Distributing or linking to modified APKs, codec packs extracted without permission, or unofficial ZIPs often violates the software’s license and intellectual property rights.