POBRApi.dll is used by the game launcher Pokemon BR, available at http://www.pokemonbr.com/ .
We have decided to not offer this file for download, since it is detected as containing viruses.
The POBRApi.dll that comes with the PokemonBR launcher (MD5 checksum: 840dfa46eb12a402e45206e933114ce6 ) , is detected as a threat by multiple Antiviruses, as seen at VirusTotal.
SOLUTION
Should you trust PokemonBR and this suspicious file, make an exception for this file at \program files\PokemonBR Launcher\ in your AV, and re-install to fix error "POBRApi.dll is missing" error.