Digging deeper into Method 1 I found that a “Scripting Guard” kicked in, which is delivered with Codestyle Pluging. It is triggered by multiple Plugins that come with Inspira, so chances are probably slim to get it working. Error messages are similar to this one :
The author uses function load_textdomain instead of load_theme_textdomain or load_child_theme_textdomain. THis may change the behaviour of WordPress, as some filters and actions are not executed anymore. Please contact the author.
This message is given for Inspira itself, but might also be triggered by redux framework in a subfolder of Inspira, as Codestyle finds a lot of translations for Inspira that are obviously redux translations.
All in all I guess using Poedit with a .pot file would be the way to go.