Question about WD Blue SN550

A clear NO! This M.2 NVME SSD achieves a maximum of 2400MB/s in read speed and a maximum of 1950MB/s in write speed and is thus far below the required 5500MB/s (read speed), which the PS5 absolutely needs in order to be able to play the games normally. You therefore need a much faster SSD.

Unfortunately, I can't answer that, because I have it installed in my PC, where it works very well and has relatively good temperatures.
of max. 40 degrees. However, I have put a heat sink on it. (2 pieces for under 6 € at Am...)

In principle, yes, but the ssd has no heat sink. According to ps5 specifications, however, the ssd should have one. So either retrofit it yourself or take an ssd that is directly equipped with a heat sink.