I understand, I only knew about KEY visual novels when they released the Rewrite brazilian translation. I had never even watched animes from KEY before. I’ve played “some short visual novels” before, but after Rewrite, I started to see visual novels in another way, I ran to play many other great works. I hope it’s the first of many for you too.
If you only want to play visual novels translated:
Planetarian - I do not know if it works with the Steam version, I tested it with the old version. It is 100%
Shuffle! - I do not know if it works with the Steam version, I tested it with the old version. It is 100%
Katawa Shoujo - Last year they released the translation. 100%. The game is free.
Umineko - I have not tested yet, but last year they released an alpha of the first episode.
Little Busters - I have not tested it yet, but it’s in the final stage of translation. Launched November last year. But they have already released a patch. Unfortunately it is only compatible with the old version of the game, it does not work with the Steam version yet.
There are many others, I just mentioned the new ones. Most visual novels on pt-br are pretty old.
There is also a good looking Brazilian visual novel called Inkey University if you want to test. Some people say it’s the best Brazilian visual novel ever made. It is free.
If you do not mind playing in English, you have many other options. Rewrite is my favorite work, my second favorite is Umineko. About KEY works, after Rewrite my favorites would be: Clannad, Kanon and Little Busters. (one day I still play Air… I swear…)