There is no single right answer.
Players will always prefer 1920x1080 if asked. But
players are idiots.
If you are
VERY good with a photo realistic render software like Daz3D or Blender, then a higher image resolution will allow you to show off that skill better. (See
Estate: Dominate, which uses 2560x1440 images as an example of that).
But you don't NEED to go that high to show off your skill. (See
Family, Friends and Strangers, which uses 1280x720).
If you are using
You must be registered to see the links
or
You must be registered to see the links
, the image size will affect your render times. So picking 1280x720 will massively improve how fast you can create each new scene. If you are using something like
Honey Select, then render times matter less... so the image size becomes less about practicality and more about personal preference. I'd say the same was true for any 2D based game, whether you are drawing by hand or using some sort of sprite generation tool.
Nobody will ever give you a hard time for using 1920x1080. But honestly, most games don't need to be any higher than 1280x720. If it's your first game, I personally would suggest 1280x720 - but be prepared for some numpty to post in the comments when you first release your game complaining that it's not 1080p.