AI Image upscaling is a Pro feature. It has been integrated in the Nero Platinum Suite subscription version and the Windows Store pro version(Watermark has been completely removed from these two products). Other products, such as the lifetime and standlone versions, still keep a Nero logo in the lower right corner. (Trial version is all Nero logo).

If you want the Pro features without the Nero logo, can purchase Nero Platinum Suite subscription version, or Nero AI Image Upscaler standlone subscription from the Windows Store:

For the un-pro version, you can manually add a blank border below the image and manually crop the logo after upscaling.