I contacted Sony Support and this is their response:
"Yes, it is possible however, it is not advisable since it may cause ghost effect due to slow shutter. Normally 1/60s is the minimum we recommend. Movie recording mode has to be set to manual instead of auto in order to enable it."
They also told me that the future has been available for a while, at least since 2014.
I hope you'll find the information helpful.
