I like the mnemonics editor that you released. But I am not a fan of changing seed words and having users meddle with words for whatever reason. It affects the randomness.
Seed words use simple English and if you don't understand what they mean it's easy to draw the letter and rewrite it without understanding what they mean. Using seeds in local languages will increase your dependency on a specific software and won't help you much because you will memorize the words on a piece of paper and not your memory.