Where do you find dark signers in yu-gi-oh tag force 4?

You can't find Dark Signers in Yu-Gi-Oh! Tag Force 4.

Dark Signers are a specific group of characters and antagonists from the Yu-Gi-Oh! 5D's anime and manga.

While the Tag Force series features characters and events from various Yu-Gi-Oh! series, Tag Force 4 focuses primarily on the Yu-Gi-Oh! GX universe.