Hi @Nicolas_Rey ,
I looked into this again and applied the solution I found here: Outputting service.name instead of / alongside context.service.name
With that, you can create an alias for the field you already have metadata.service.name to service.name.
I tested this with my sample application and it looks promising:
(note: I aliased from fields.service.name to service.name)
Maybe @Martijn_Laarman has a better solution but this is the workaround I can suggest at the moment.
Cheers,
Wolfgang