There has been no credible evidence or reliable reports indicating that Beyoncé warned Kim Kardashian about going after Blue Ivy’s career. This appears to be a rumor or speculation without any substantial basis.

Beyoncé and Kim Kardashian are both high-profile celebrities, and their interactions, as well as those of their families, often attract significant media attention. However, it’s important to rely on verified sources and avoid spreading unconfirmed gossip. As of now, there have been no verified incidents or statements from Beyoncé regarding any warning to Kim Kardashian about Blue Ivy.

If you have more specific details or context about where this information might have come from, I can look into it further for you.