Phases in GroupShare are fixed and not customizable. Because each translation vendor has its own translation process, adding custom phases should be possible.
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This is a duplicate of https://community.sdl.com/solutions/language/translationproductivity/translation-productivity-ideas/i/studio-groupshare-ideas/changing-the-number-of-phases-and-their-names-in-groupshare
Phases in GroupShare are fixed and not customizable. Because each translation vendor has its own translation process, adding custom phases should be possible.