Well you might actually be able to do it, but it would need some things to make it work.
First you would need to be able to upgrade the phone to the Marshmallow OS (operating system), and it would have to be a phone that Samsung hasn't restricted.
Some phone companies have made it so that even though you can (in Marshmallow only) format the SD card to be "Internal" rather than "External", some of them have put limitations on the phone to keep it from working. Not all, but many.
I can't say if yours would have the limitation. But "If" you can upgrade the OS to Marshmallow, you would be able to try. Before spending the money on a new phone that is.
Good Luck!