I manually input phrases on OneSky's online platform, but when I try to export them and select a file format, there are many encoding issues and extra characters which could break my code.
The manual input feature is meant for testing phrases on our site, not meant for an official localization workflow or a file conversion platform. All phrases should exist in string files, generated from internationalizing your app.
Internationalize your app, grab those generated string files (.xml, .strings, .po, etc.), and upload them onto our website.