I have a thought on the max current items which caused the cant-emove-infinite-equipped-item issue, more likely the onhand item quantity is maxed and u cant unequip your current equipped item becuz the item qty is maxed at 99,so sell an item of it may fixed the issue, i may give it a try on coming weekend
*UPDATE*
I managed to hack all medals in my item medal list but no trophy pops even I sold all my medals to medal man... I googled out about the medal trophy system works,it seems the game registering its count when you collected any new medals, so NOT selling to medal man to pop the trophy.
*UPDATE 2*
I managed to pull certain data section from a DLCed save and put to my save and medals trophy pops ,but do note here, it pops 500 medals(400/300/200/100) specifically only, it will not pops all at a same time,so good luck