on SAI if you try to transform a selection, there is 4 buttons that appear to help you do easy tasks quickly : Flip Horizontally/Vertically, Rotate 90° CW/CCW (they appear in the equivalent of the "tool options" panel in Krita)

Adding at least the Flip Horizontally/Vertically buttons would be very convenient, so people wouldn't have to lose time clicking on Rotate, then carefully adjusting X/Y to be exactly 180 in the tool options.
Could it be done?

sorry if this is not the right forum for requests.

+1 for buttons having common transform like horizontal and vertical flip and 90° rotate , they can be in the tool options for transformation.

i've never used sai myself, but it sounds cool

+1 from me too.

Interestingly, we've gone back and forth on making the layer rotate and flip actions act on the whole layer or the selected pixels. Some want it one way, others, the other way, it seems.

Boud, can both exist , the layer menu will have layer flip option, the transform option docker will have flip buttons for the pixels which have transform activated , the main goal is to reduce the time required for simple and recurring transform actions like flip and rotate 90 degree.

Sure, all it needs is time for coding

These are really neat ideas. If we start doing this, it would be nice to think about the transform tool in general. The tool options with the transform tool are a monster. There are multiple modes, as well as a ton of options with each mode.

offcourse,
A wish bug then

sorry, it's my first time requesting a feature. I am glad to see others agreed to my idea.
so should I fill a bug request (with wishlist in severity) now?
thanks in advance.

Yes, please do!