Finally, I managed to find several listings for 12″ Hero Series figures as well as role play items, when cross referenced with each other, they may confirm that Kylo Ren’s LFL product code name is “Olso”.

12″ Hero Series
E9 “Bruges Red”
E9 “Oslo”
E9 Darth Vader

Role Play
E9 “Oslo” Mask (Kylo Ren?)
E9 Stormtrooper Mask
E9 Darth Vader

The relevant UPCs and Walmart SKUs have been added to our Master List for your reference.