XNA to Monogame Guassian Blur Effect broken

Graphics
3

The input you take in the pixel shader must match the output of the vertex shader. In the case of a SpriteEffect the vertex shader is the one used by SpriteBatch. Its output is the following:

struct VertexShaderOutput
{
	float4 Position : SV_POSITION;
	float4 Color : COLOR0;
	float2 TextureCoordinates : TEXCOORD0;
};

If you modify your code to make that the type of the input, does it fix your issue?