Would like to add a door, need input

[prefers shiners]

Pocket door would be problematic.... Would require slot of demolition and rebuilding wiring. From what I see here in the pictures provided there probably isn't enough wall space for a pocket door to slide into the wall. It appears as though you have about a 36 inch wide opening and if you're handy with tools, there would be plenty of room to install a hinged door from kitchen into laundry room.
The proper hinge side of door should be on left side of opening and swinging into laundry room with the doorknob on the right-hand side. However.... From the pictures provided it looks like the refrigerator would be in the way of the door knob. So the solution would be to hinge on right-hand side swinging into the laundry. This would only create issues primarily from a convenience perspective as you would opening the door across direction of travel towards the center of the laundry room instead of towards a perpendicular wall as is common.

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I pretty much agree with these comments. Couple of things to remember....measure your current opening to verify if it is a standard door opening....if so, then you are OK.....otherwise, the door will have to be custom built or the opening will have to be modified....if the opening is a standard size opening, I like the idea of buying a pre-hung door complete with door attached to jambs....if you decide to keep the existing door jambs & trim so that it matches existing wood in the room, then you have a serious job of buying just a door and notching the existing wood for the hinges...personally, I would not tackle this....to much alignment to do....to much to go wrong....OK, so I like the pre-hung door....only thing is, you have to stain the new jambs to match the existing wood, or, try to talk your wife into living with a painted door, jambs and trim....you can remove and re-use the trim around the door but be very careful not to damage it...so, hinges on left side, swing door into laundry room, move refrig to make room for knob....also your main purpose for the door is a sound barrier....none of the other doors will give you that....use a solid door...maybe even consider an exterior door that comes with rubber seals around the top & sides and add a seal on the bottom...last, get a door and frame that is solid wood....stay away from any particle board wood that screws will work loose...if you are going to do the work, make sure that it does the job you want....seems like a simple job but a lot to think about....good luck...