What are some alternatives?
When comparing POEditor and Transifex, you can also consider the following products
Crowdin - Localize your product in a seamless way
Poedit - Poedit translations editor. The best way to translate apps and sites.
Smartling - Website localization & translation
Lokalise - Localization tool for software developers. Web-based collaborative multi-platform editor, API/CLI, numerous plugins, iOS and Android SDK.
Pootle - Multiple file formats.
OneSky - Full Stack Localization Solution