Probably they will use the new Vega64 Architecture with the newer AMD APUs.
I bet its going to be a modified AMD 2200G APU
Well, yeah, one like a AMD 3400G APU (the first number is the series)... but based on zen3 manufactured at 7nm and with NAVI graphics cores
AMD already have the zen3 design completed, some weeks ago AMD was talking about how the teams works internally... they have two big teams working on paralell and while one team was working in zen2 the other was working in zen3 (intended to be released some years afer zen2)
The two big problems for VEGA in dedicated graphic cards is the high temperature and high TDP... but this is going to be solved easilly when they jumps to 7nm, also look at the vega chips for laptops and mobile (are APUs labeled mobile, or mobile pro)... are very efficient right now
Both zen3 and NAVI are dated to be released to public in 2020 or so... but for sure AMD has some prototypes already (build on 14nm or 12nm)
The way AMD is working now with sony and microsoft is by offering them a basic "layout" of the internal circuits of the APU divided in "blocks"... basically is the same circuitry design that is going to be "printed" on the silicon mineral (with some fotosensitive technology and chemicals)
They sends that "drawing" divided in blocks and the other company (sony or microsoft) chooses which "blocks" they wants and which ones they doesnt wants... together with a huge list of specs
You can choose how many cores you want, the widths of buses, caches sizes, instruction sets, and lot other details like that
The point is AMD is not going to build an APU "from scratch" for them... is going to be based in the design of zen3
And if is true what this news says i guess what they are going to do is to add more cores dedicated to the system (and emulation controll)... this way all the other cores are dedicated to the game
In a emulator they asigns a specific task for every core (so every core emulates a component of the emulated console)... so the most number of cores you have (and the code separated in specific threads) the performance is going to be better
So i guess is going to be something like that... and AMD APU based on zen3 with lot of cores, NAVI graphics, and high frequencies and huge data buses (and eventually HBM3 memory dedicated to graphics)
By now is a bit soon to provide sony and microsoft with something like that, ths is why i said in other thread is a bit soon for the devkits, because distributing devkits means the final specs of the PS5 are finalised, and i dont think is finalised yet... but they should be close because AMD can do it right now... is just building a APU prototype like this is going to be too much expensive... but they should have at least one or two already working that have been sent to sony and microsoft