These are tiny files (usually a few MBs). They act as digital tickets. They tell the Switch: "The user owns Kombat Pack 2." These are often bundled under a title like "Mortal Kombat 11 [0100F2200C984800][v196608][DLC].nsp" .
Before you spend hours hunting down a 30 GB update file on slow file-hosting sites (like 1fichier or Uptobox), consider the legitimate route. mortal kombat 11 switch nsp dlc update 1026 free
Mortal Kombat 11 Ultimate (Physical Cartridge) Nintendo released a physical cartridge of MK11 Ultimate. This cartridge ships with Update 1.0.26 already on the card. You do not need to download anything. These are tiny files (usually a few MBs)
The eShop Sale MK11 Ultimate frequently goes on sale for 70% off (around $20). This includes every character, skin pack, and the Aftermath story. The eShop Sale MK11 Ultimate frequently goes on
The specific update you're mentioning seems to refer to a patch or an update version. Game updates often include bug fixes, balance changes, and sometimes new content. However, without more specific details, it's challenging to provide information on what exactly update 1026 entails.