Depending on how your exported PNGs are going to be used, you may need to change the colour profile setting, which you can do by choosing an option from the PNG Color Profile select box:
- Display P3 (Max Compatibility)
- Display P3 (Max Correctness)
- DCI-P3
- Adobe RGB (1998)
- Apple RGB
- ColorMatch RGB
- Wide Gamut RGB
- CMYK
- sRGB
- sGrey
- ProPhoto RGB