Whelp, i found a workaround, not a nice one, but at least it works. RenderTargets can have pretty much everything edited, including Texture Group and Filter Settings, so the trick is to use the imported texture in the Material, then use this material to draw onto a RenderTarget, Edit the settings of this RenderTarget like changing the Texture Group and Filter, then use this edited RenderTarget as new texture input for the Material.
So you have to set the RuntimeTexture twice, first with the blurry one, then again with the not blurry RenderTarget.
