Shader Passes

Hey i write a little 2D outline shader, but my problem is that i use multiple Passes, so dynamic batching do not work and thats bad for performance.

This is one Pass, i just draw the vertexes like 4 times, x+spread, x-spread,y+spread, y-spread. Than in the last Pass i paint the sprite in his normal color in the middle and i have a nice outline. Is ther a way to combine my passes ? If yes how can i do that?

Pass 1-4 loks like this (this is the case: vertex.x + spread):

 Pass{
                 CGPROGRAM
                 #pragma vertex vert
                 #pragma fragment frag
                 #pragma multi_compile DUMMY PIXELSNAP_ON
                 #include "UnityCG.cginc"
 
                     struct appdata_t
                     {
                         float4 vertex   : POSITION;
                         float4 color    : COLOR;
                         float2 texcoord : TEXCOORD0;
                     };
 
                     struct v2f
                     {
                         float4 vertex   : SV_POSITION;
                         fixed4 color : COLOR;
                         half2 texcoord  : TEXCOORD0;
                     };
 
                     fixed4 _Color;
                     float _OutLineSpread;
 
                     v2f vert(appdata_t IN)
                     {
                         v2f OUT;
                         float4 vertex = float4(IN.vertex.x , IN.vertex.y , IN.vertex.z, 1);
                         vertex += float4(vertex.x + _OutLineSpread, vertex.y, vertex.z, 1);
 
                         OUT.vertex = mul(UNITY_MATRIX_MVP, vertex);
                          
 
                         OUT.texcoord = IN.texcoord;
                         OUT.color = IN.color * _Color;
                         return OUT;
                     }
 
                     sampler2D _MainTex;
 
                     fixed4 frag(v2f IN) : SV_Target
                     {
                         fixed4 c = tex2D(_MainTex, IN.texcoord);
                     _Color *= c.a;
                     return _Color;
                     }
                     ENDCG
                  }

And the last Pass loks like this:

 Pass{
                     CGPROGRAM
                     #pragma vertex vert
                     #pragma fragment frag
                     #pragma multi_compile DUMMY PIXELSNAP_ON
                     #include "UnityCG.cginc"
 
                     struct appdata_t
                     {
                         float4 vertex   : POSITION;
                         float4 color    : COLOR;
                         float2 texcoord : TEXCOORD0;
                     };
 
                     struct v2f
                     {
                         float4 vertex   : SV_POSITION;
                         fixed4 color : COLOR;
                         half2 texcoord  : TEXCOORD0;
                     };
 
                     fixed4 _Color;
                     float _OutLineSpreadX;
                     float _OutLineSpreadY;
 
                     v2f vert(appdata_t IN)
                     {
                         v2f OUT;
                         OUT.vertex = mul(UNITY_MATRIX_MVP, IN.vertex);
                         OUT.texcoord = IN.texcoord ;
                         OUT.color = IN.color;
 
                         return OUT;
                     }
 
                     sampler2D _MainTex;
 
                     fixed4 frag(v2f IN) : SV_Target
                     {
                         fixed4 c = tex2D(_MainTex, IN.texcoord);
                         c.rgb *= c.a;
                         return c;
                     }
                         ENDCG
                 }
 
         }