German is a difficult language to learn. If ou did learn it, you would suddenly begin to see something interesting things about English.
The latin and greek we use in English becomes readily apparent.
Actually the word "Recht" is almost exactly equivalent in English. It means "rights" "correct" and "Rechts" indicates a "right-hand turn for instance".
I used the term Justice, because that is what is closer to the meaning in the given circumstance, but "right" can also mean justice.
When you want to be as clear as possible in English, always better to use the word with Germanic routes. When you want to sound flowery, use the latin.
Actually these 3 words are quite similar to their English cognates.
Einigkeit: Ein means one, and comes from the some root, as does the Latin root uno in "unity." Einigkeit means literally "one-ness."
Recht: Very similar to English "right," especially when you consider that the "gh" in the English word was once pronounced, sounding not unlike the German "ch".
Freiheit: Again, the root adjective "frei" is almost identical to the English "free." "Heit' and "keit" are simply German suffixes for converting adjectives to nouns.
The Angles, Saxons, and Jutes who brought English to Britain came from N. Germany and adjacent Denmark. I've read that Old English, Old German, and Old Norse were so similar that they were mutually intelligible.