Subaru pistons can be removed without block disassembly or connecting rod removal as they’re Boxer style engines. There are holes (sealed by plugs) in the block both front and rear on each side. A wrist pin circlip is removed from each hole and the wrist pin withdrawn through the hole with the piston being somewhat awkwardly forced out of the top of the bore.
The downsides are that a special factory tool is needed for wrist pin removal (although that can be worked around) and that any cylinder honing as to be done with great care as the end of the connecting rod still occupies a spot in the cylinder bore. It’s also a bit awkward to line that connecting rod small end back up with the wrist pin holes in the piston during assembly
Still, makes no sense to go into pistons at almost 200k miles because more than likely the cylinder bores are out of spec in one way or the other.