The version number "v1.3" is commonly associated with community-made tools and guides for the official game, rather than a standalone PC executable:
Unofficial recipe web apps (v1.3) exist to help filter ingredients. Pokeman Quest v1.3.exe
A popular community v1.3 cooking recipe list was widely shared to help players attract specific Pokémon. The version number "v1
If you are looking to play on PC, it is much safer to download the official APK from the Google Play Store and run it through a reputable emulator. unofficial fan-made project.
Even if it isn't malicious, it may simply be a bundled emulator or a very early, unofficial fan-made project.