Plants depends partly on location
This question is a bit more complex than it looks, since it depends partly on location. In Alaska, a full-shade plant might do best in dappled shade. In Florida a full-sun plant may well need some afternoon shade. The specific location can make a difference too; full-sun plants near light colored walls and patios may be able to take more shade because they get reflected light.
In general, most sun plants need at least five hours of full sun per day during the growing season. It doesn’t matter when they get shade as long as they receive at least five hours of sunlight. Any less, and plants will most likely show little growth or vigor, fewer or no blooms and have a thin, spindly appearance.
Most shade plants can handle morning sun (before 10 a.m.) and late afternoon sun (after 5 p.m.)-but no direct sunlight between those hours. Shade plants that are exposed to direct sunlight for more than 20-30 minutes during these midday hours will generally burn, with the leaves exhibiting leaf scorch spots or burning completely brown.
If you have a plant that you discover is in the wrong location, wait until the early evening hours to transplant to a more appropriate spot. (If it’s a shade plant in too much sun, try to shade it with something until you can get it moved.)