Highlight Effect

Just go to your desired node cgo under material click on new shader than click on just created shader and again click on Make new shader and copy paste this code

i just updated it for 3.6x it was orignially made by Oni_The_Demon

Shader code

shader_type canvas_item;
render_mode blend_premul_alpha;

uniform float Line_Smoothness : hint_range(0, 0.1) = 0.045;
uniform float Line_Width : hint_range(0, 0.2) = 0.09;
uniform float Brightness = 3.0;
uniform float Rotation_deg : hint_range(-90, 90) = 30;
uniform float Distortion : hint_range(1, 2) = 1.8;
uniform float Speed = 0.7;
uniform float Position : hint_range(0, 1) = 0;
uniform float Position_Min = 0.25;
uniform float Position_Max = 0.5;
uniform float Alpha : hint_range(0, 1) = 1;

void fragment() {
    // Calculate center and gradient towards edges
    vec2 center_uv = UV - vec2(0.5, 0.5);
    float gradient_to_edge = max(abs(center_uv.x), abs(center_uv.y));
    gradient_to_edge = gradient_to_edge * Distortion;
    gradient_to_edge = 1.0 - gradient_to_edge;
    
    // Apply rotation based on Rotation_deg
    float rotation_radians = radians(Rotation_deg);
    mat2 rotation_matrix = mat2(vec2(cos(rotation_radians), sin(rotation_radians)),
                                vec2(-sin(rotation_radians), cos(rotation_radians)));
    vec2 rotated_uv = rotation_matrix * center_uv;

    // Remap position for dynamic effect
    float output_range = Position_Max - Position_Min;
    float remapped_position = Position_Min + output_range * Position;

    // Animate the texture offset over time
    float remapped_time = fract(TIME * Speed + remapped_position);
    remapped_time = -2.0 + 4.0 * remapped_time;

    // Calculate offset UV and line effect
    vec2 offset_uv = rotated_uv + vec2(remapped_time, 0.0);
    float line = abs(offset_uv.x);
    line = gradient_to_edge * line;
    line = sqrt(line);

    // Adjust line width and smoothness
    float line_smoothness = clamp(Line_Smoothness, 0.001, 1.0);
    float offset_plus = Line_Width + line_smoothness;
    float offset_minus = Line_Width - line_smoothness;

    // Remap the line effect for highlight
    float remapped_line = (line - offset_plus) / (offset_minus - offset_plus);
    remapped_line = clamp(remapped_line, 0.0, 1.0);

    // Apply the highlight effect to the texture, not the background
    vec4 tex_color = texture(TEXTURE, UV);
    tex_color.rgb += vec3(remapped_line) * Brightness; // Apply the highlight effect directly to the texture

    // Keep the original alpha channel intact
    tex_color.a *= Alpha;

    // Output the final color
    COLOR = tex_color;
}