A modder of Nexus Mods is helping players add their cat to the PC version of Stray. The modder NorskPL accept commissions to build your cat from scratch and drop it into the game developed by BlueTwelve Studios and published by Annapurna.

Several people have already applied for the skills of NorskPL, which loads all of its creations onto his own official page from where you can also download and use them. At the moment there are not many creations but almost certainly, over time, the page will fill up more and more.

Even before the publication, Annapurna Interactive had confirmed that there would be no customization options, given that Stray tells "The adventure of this particular cat". Presumably this statement also rules out the possibility of seeing themed DLCs in the future.