Recommended size: 1024 x 1024

Prompts:

charavxace, chibi, multiple views, full body, standing, simple background,

In this link you can rescale the image (Pixel Size 8) and reduce the color palette:

https://pixelartvillage.com/

Alternatively:

Recommended extensions (Automatic1111/ Forge):

For perfect rescaling:

stable-diffusion-webui-pixelization

To reduce the color palette:

sd-webui-pixelart

Recommended program to edit pixelart:

Graphicsgale