Cross-processing
In film photography, this term refers to the process of processing color negative film in reversal film (E6) chemicals or color reversal film in negative film (C41) chemicals. Sometimes, this technique is referred to as "X-Pro." The ensuing variations in color gave the photos a one-of-a-kind appearance. The approach used to be particularly well-liked in the field of fashion photography. Increasing the contrast and making adjustments to the color channels in Photoshop can provide an appearance that is virtually identical.
Do you have a better definition? Share it in the comments.