Posted 29 December 2017 - 12:31 AM
E Mount has a shorter flange distance than A Mount. Therefore, E Mount lenses focus in front of the sensor on an A Mount camera. The only way to push focus back onto the sensor would be an adapter with an extra lens. This means that you lose autofocus and ruin the image quality. There are some adapters of this sort around, for instance Minolta to Canon. But they're generally useless.
The best option, if you're interested in FE lenses is to buy a spare FE Mount camera and the FE lenses you're interested in. You can always adapt your A-Mount lenses for more choice. I did so for a while but to me it was more trouble than it was worth. I got rid of my full frame E Mount gear and my APS-C A Mount gear. So now I use A Mount for full frame and E Mount for APS-C. To me, that's optimal in terms of size, handling and performance. Occassionally, I adapt full frame A Mount lenses to my APS-C E Mount cameras, but that's mainly for macro shots when the smaller camera comes in handy, i.e. low to the ground and such.