Unfortunately, you cannot include a URL or QR code that leads to another side or app in your World.
However, you may include a brand logo, related image, etc. that represents a group in your World. In this case, please contact customer service when submitting your World for review.
Please review the link below for Worlds created for promoting a group/company.
▶︎ [Studio - World] Can I create a World with the purpose of advertising or hosting an event for a company or a group?
Please find the ZEPETO review guidelines in the following link. This will ensure a smooth review process.