is it possible to export sprites as png?

Title is self explaining i guess :)

sure,

you can do it in code:

system.file.save(sprites['icon'].frames[0], 'icon.png')

more in the docs https://microstudio.dev/documentation/API-cheatsheet/ in Save Image

or straight from the browser by adding sprites/sprite_name.png to the project game page (in microstudio.io)

e.g https://microstudio.io/KingLauri200/scotlandyardsim/sprites/poster.png