I did say in an earlier post...
"The way this relates to the OP is that I think you can use a 28mm on APS-C and get pretty close to what you'd get with a 50mm on FF except the thin DoF at the widest apertures. The way to try and match the DoF would be to live with the different framing and reduce the camera to subject distance."
But I wasn't replying to that post but one where you mentioned keeping framing the same.
Not that I'd want to try and teach anyone to suck eggs but most people here would probably know that using a smaller format means using wider lenses to maintain the same FoV and that this will alter the DoF. My point was that if shallow DoF is your aim you can get it by reducing your camera to subject distance (or using a longer lens) if you can live with the different framing.
If shallow DoF is your aim, use a bigger sensor or wider aperture is the better suggestion as moving closer gives you a different picture. Possibly one that doesn't work for example - if doing head shots and you want a shallow depth of field and try and move in close, then the perspective you get may then be unsuitable for a head shot.
Personally I think that the DoF argument regarding CSC has been done to death and is almost certainly not as big an issue for most people as posts in forums would suggest and of course there can be advantages in using a smaller format... you can get about the same DoF (equiv to FF at something between f2-2.8 ) if not exactly the same look with wider apertures that allow the use of lower ISO settings and/or faster shutter speeds
The difference between FF and the next sensor size down is quite marked, even more so with the smaller formats when it comes to DoF. And despite what you say, it is very hard to make smaller sensor shots look like FF, particularly with non-telephoto shots.
Unless you actually alter the optics such as is done with the metabones speed booster.
I'd take some shots to demonstrate the difference, but I gave my crop sensor camera away after it gathered dust for several years. And it didn't get used because the difference between it and my FF camera is in fact very marked, obviously not in a good way.