While there are no hard and fast rules for what constitutes a "fair use" of copyrighted material, there are "four factors" which courts consider, which can be summarized as follows:
- Using a small portion of a work is favorable to using a substantial portion. If there is a high degree of similarity to the original work and your submitted work it'd be a case of infringement.
- Use of a work to provide commentary in an educational setting is favorable to using a work for commercial enterprise.
- Use of factual works is favored over using creative works of fiction.
- Minimal or negligible impact on the market for the work is generally viewed favorably.
If either of the 4 factors listed are present in your work, we'd caution you to treat the item as infringing copyright.
As a side note, a lot of the recognizable IP that you see on other marketplaces and apps like Etsy/Redbubble/Ebay/VRChat etc. is infringing. It's just not taken down unless/until the copyright owner makes a complaint.
