When the name of the user is not listed, it should be the neutral form.
There should be no GENDER when the user name is not shown or could not derived from context (like in navigation menu of user pages)
emailuser is used in navigation menu, the context is set to the user.
For a message about rejecting translation or other things there is no context and the question is why it should use gender form, when the reader does not see for which user it is.
No open question in this task hence resetting status from stalled to open.
However, task could be declined due to last comment ("the effort to make it work [...] is very high compared to the potential benefits.").