this is not so easy, because it is not a translation, it’s a change.
You would need to modify the base template strings and then change the translation.
We don’t translate english strings at all, because “the source” is english. Thats why you have to change the base template. Which would result in problems after an update.
Do you think its’ a good idea to accomplish this, if I change the system language to Deutsch and copy and paste everything into English and only change the terms I want?
No I don’t think that would help. As I wrote, you need to modify the templates to change the translated strings and not modify the translation. An “Organization” is an “Organisation” in german as for a “Company” it’s “Firma”.