When the first trailers for Rogue One appeared, people took to social media and made jokes about there not being any Bothans in the trailers. Either these people aren’t serious Star Wars fans, or they’re just not remembering Return of the Jedi correctly and the fact that there were two (ok now three) Death Stars in Star Wars.
Mon Mothma in Return of the Jedi explains the Bothan’s role in the second Death Star:
“The data brought to us by the Bothan spies pinpoints the exact location of the Emperor’s new battle station. We also know that the weapon systems of this Death Star are not yet operational. With the Imperial Fleet spread throughout the galaxy in a vain effort to engage us, it is relatively unprotected. But most important of all, we’ve learned that the Emperor himself is personally overseeing the final stages of the construction of this Death Star.”
If you really analyze that dialog, it sounds like the Bothan spies actually just found out where the second Death Star was and the crucial fact that the Emperor was overseeing construction. She actually never says that the Bothans stole any plans.