For example, you have planets in 5 degrees Aries and 5 degrees Virgo both are in quincunx at natal. There is a possiblity by progression one is faster and one is slower at some point the antiscia degree can be perfected in the progression but the foundation of this two planets were in quincunx only at some point in life they also becoming antiscia. So the interpretation will be based on the original disharmony or lack of common interest to become best mates later on.
The same could occur between natal planets between Libra and Pisces as they have large degrees of distance so more likely to experience antiscia relationship early by progression. But then that will be based on the condition in natal and motion/speed/direction of the planet how and when they will perfect this antisicia relationship. Such as contra antiscia certain signs may form conjunction as well as contra antiscia.