The black outline or shadows around textures after importing Spine exports into Unity could be due to a mismatch between the texture export settings from Spine and the import settings in Unity, specifically regarding Premultiplied Alpha (PMA) and Straight Alpha settings. Ensure that your Spine export settings match your Unity import settings. If you are using PMA textures, make sure that Unity's texture and material settings are correctly configured for PMA, and that you are not using Linear color space with PMA textures, as it is not supported. Additionally, check if the Alpha is Transparency setting in Unity's texture import settings is correctly set according to your workflow (disabled for PMA). If the issue persists, it might be helpful to review the spine-unity runtime documentation on Premultiplied vs Straight Alpha Import.
