I have the following power supply https://www.aliexpress.com/item/60W-Dua ... 35968.html
The 5V option is rated for 4A with a range of 0.3A-6A.
Will this cook my Raspberry Pi 3 B+ or should it be fine?
How do you conclude that? It can be adjusted to deliver 5.5V, but the spec says total combined voltage tolerance is 2%. If you don't want voltage above 5.25V, don't adjust it to above about 5.15V
You misunderstand the specification. The 5V is adjustable (Voltage Adj Range) from 4.75V to 5.5V by turning a potentiometer with a screwdriver. See the orange part on the front panel marked +V ADJ.