When adding a template to the translation, Content Translation looks for the equivalent template using Wikidata. In case the process fails, T192271 describes how to communicate what went wrong to the user. When the equivalent template is found, the information is transferred to the equivalent target parameters, using TemplateData for the mapping. In this process only parameters that exist in the target template should be added to the template.
Currently, when adapting an infobox template, a parameter from [[ https://en.wikipedia.org/wiki/Template:Infobox_person | the original template ]] ("image") that do not exist in [[ https://ca.wikipedia.org/wiki/Plantilla:Infotaula_persona | the target template ]] (note that the equivalent parameter is "imatge" instead) was added. An error message is shown as part of the target template (tested by translating "Uma Thurman" from English to Catalan in production):
The resulting wikitext ("infotaula-persona" is the template generated):
The expected result would be to either (a) use the parameters as defined in the target template, or (b) have the parameters missing. In any case, we should not add parameters to the target template that do not exist in such template.
For the particular case used in the example, the preferred adaptation would be to add the template without parameters since the target template is based on Wikidata, which means that information for missing parameters are queried from Wikidata (which is preferred since it reduces redundancy). The support for Wikidata-based templates is part of a separate ticket.