en_tn/ecc/03/16.md

I have seen the wickedness ... wickedness was there

These two phrases mean the same thing and emphasize how common wicked behavior is. (See: rc://en/ta/man/translate/figs-parallelism)

in place of righteousness

"where there should be righteousness"

under the sun

This refers to things that are done on earth. See how you translated this in Ecclesiastes 1:3. Alternate translation: "on the earth" (See: rc://en/ta/man/translate/figs-idiom)