You will be able to find a range of free and paid for online training via Google. You can find some recommended resources below.
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TAUS is an independent organization which that shares knowledge, metrics and data to support people and businesses doing translations and related activities. TAUS offers a range of resources and training, including online courses on post-editing and quality management of translations: https://elearning.taus.net/course/index.php. These courses come with a fee.
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