First, you need a turntable that rotates at 78 RPM.
Solve that and then the rest will fall into place.
It goes futher than just speed...
...but, as markw stated, you need a 78rpm setting o-r i-t w-i-l-l s-o-u-n-d m-u-ch s-l-o-w-e-r and the pitch will drop roughly an octave or more...
Then we get into the whole stylus shape and how modern eliptical styli may bounce around the wider/deeper grooves or the cantilever itself may contact the record's surface...
So, no, there is no add-on device that will do this and folks who do have a collection of 78s(as I do) usually will have a tt/cart combo dedicated specifically for this purpose...and then of course we have the different EQ curves involved...don't ask...
And good luck trying to find someting to play those 16rpm Lithuanian language lessons...
jimHJJ(...listen anf repeat...sesu...yes...sesu...yes...)