If you are using
bitnami as the FileZilla user, you should be able to edit/upload files to
/opt/bitnami/apps/wordpress/htdocs/wp-content/languages/ because you have the proper permissions.
In your first message, the error is related to this file:
xstore-pt_BR.mo. But in the output of your
ls -la command I can't see this file, are you trying to upload it or it should be previously on the server?
ls -la command, I can see
-rw-rw-r-- 1 here bitnami 45405 Jan 21 01:57 admin-network-en.br
here user? Is it the user using FileZilla? You shouldn't have any file in this folder with user/groups different to
bitnami/daemon, to solve it, can you run the following command?
sudo chown -R bitnami:daemon /opt/bitnami/apps/wordpress/htdocs/wp-content/languages/
Anyway, it seems that appears any issue with the above command to change the permissions, can you execute the following command?
sudo chmod -R o+w /opt/bitnami/apps/wordpress/htdocs/wp-content/languages/
Carlos R. Hernández