I've got a special "Dashboard" node that consists of entity references to other node types. In dashboard form mode all widgets are configured to use Entity Browser to display an (Inline Entity-) form in a modal popup. (So all child entities are editing in a popup window, opened with a click inside the dashboard node). This works fine for my main language.
I need to enable translation capabilities for the referenced entities from within my Dashboard node. I've enabled translation for all referenced entities. But my editors do not have access to content overview, they need to do the translation from somewhere within the dashboard node UI. But neither EB nore IEF have any options to display a translation button or translation tab. There are options for edit/replace/remove, but no "embedded" translation.
(To emphasize: The dashboard node is just some sort of container node with untranslatable ER fields. I need translation for the referenced entities, but accessible/clickable starting from somewhere inside the dashboard node edit form).
What is the best starting point to add a translation link/button for the child entities? I can think of two options: Modify the EB field widget and add a translate button in the parent form, or add a local task in the popup modal edit form of the child entity.
I've done some simple form hooking and simple fields (-widgets), but TBH I've no clue at all with complex stuff like EB and IEF, and would be grateful for any hints directing me to a good starting point.