According to information from its GitHub page and Discord channel, work on PS4Delta started sometime this August and is currently in very early stages meaning that it wonít let you play or even boot any PS4 games just yet. Contrary to other emulation solutions, PS4Delta is not an emulator in the traditional sense but a compatibility layer similar to WINE in which HLE (High Level Emulation) is achieved rather than LLE (Low Level Emulation) meaning that it doesnít work by imitating the behaviour of PS4 hardware devices through virtualisation.
However, it works by translating PS4 system calls into native calls for Windows which is possible because the PS4 uses x86-64 architecture which is the same one used by the vast majority of modern PCs. On a different note, itís important to mention that PS4Delta is completely open-source and written in C++ so anybody with knowledge in emulation can contribute to its development. (GitHub link below)

PS4Deltaís Discord Invite (discussion about whatís going on):
PS4Deltaís GitHub (source code):