My configuration: latest dev entity translation and field collection module + patch.
1. Entity translation is on just for taxonomy term and node, but not for field collection (it triggers notice: not translatable because of valid base path...) I have taxonomy term with field collection (unlimited value). In FC field there are just two fields that needs to be translated. FC and fields inside FC have set "enable field translation by users".
With these settings I can create a term, set values to FC fields on default language and save. Then I can translate and set values to FC fields for second language and save. All good when checking if it did saved 2 different values - each for own language. Then I create view which is used on panels and is using termID as context filter. View has relationship on FC field and I added FC fields to show. What happens: on view when I preview with term ID (context filter) I get correct result for the language in URL (en/admin/structure/views..). Also when I change URL to another language prefix I get translated fields in that language. But translated fields don't show on actual term pages.
2. Beside what I described in 1, I also enable entity translation for field collection. Notice about valid base path is still there, but I applied patch and i don't get errors when adding or translating FC.
With this configuration I create fresh FC with new fields and enable field translation for all of them. On term I set some values for FC fields and save it. I repeat this step when translating. But when I save translations and open them they are empty. On the next fill they remain. But the view for this configuration is still not showing right values for selected languages.
Does anyone have any hint what I am doing wrong? I really need to fix this issue on my site and I am short on time.