Change default Icon of LWC Component with SVG icon

Yes, we can change Lighting web component default Icon to some custom svg icons for Lightning App Builder and Experience Builder.  

Change default Icon of LWC

Step: 1

In your lightning web component add a new file with same name of your component with .svg.

componentName.svg

Step: 2

Add your svg resource code in that file.

Step:3

Now open lightning app builder and check the component.

Let's see with an example to know more about svg icon for lwc component.

helloWorld.html

<template>
   <lightning-card title="Hello World" icon-name="standard:account">
      <div class="slds-m-around_medium">
         <lightning-input label="Name" value={myName} onchange={handleNameChange}></lightning-input>
         <h1>Hello {myName}</h1>
      </div>
   </lightning-card>
</template>

helloWorld.js

import { LightningElement, track } from 'lwc';

export default class HelloWorld extends LightningElement {
   @track myName;

   handleNameChange(event){
      this.myName = event.target.value;
   }
}

helloWorld.js-meta.xml

<?xml version="1.0" encoding="UTF-8" ?>
<LightningComponentBundle xmlns="http://soap.sforce.com/2006/04/metadata" fqn="helloWorld">
    <apiVersion>46.0</apiVersion>
    <isExposed>true</isExposed>
    <targets>
        <target>lightning__AppPage</target>
        <target>lightning__RecordPage</target> 
        <target>lightning__HomePage</target>
    </targets>
</LightningComponentBundle>

helloWorld.svg

<svg xmlns="http://www.w3.org/2000/svg" width="200" height="140" viewBox="0 0 200 140">
    <path fill="#00A1E0" d="M 83.226562 15.273438 C 89.679688 8.554688 98.660156 4.382812 108.589844 4.382812 C 121.792969 4.382812 133.308594 11.746094 139.445312 22.675781 C 144.773438 20.292969 150.675781 18.96875 156.882812 18.96875 C 180.695312 18.96875 200 38.441406 200 62.460938 C 200 86.484375 180.695312 105.957031 156.882812 105.957031 C 154.03125 105.957031 151.1875 105.675781 148.390625 105.109375 C 142.988281 114.746094 132.695312 121.257812 120.878906 121.257812 C 115.933594 121.257812 111.257812 120.113281 107.089844 118.082031 C 101.617188 130.960938 88.859375 139.992188 73.988281 139.992188 C 58.503906 139.992188 45.308594 130.195312 40.242188 116.457031 C 38.027344 116.925781 35.734375 117.171875 33.382812 117.171875 C 14.945312 117.171875 0 102.070312 0 83.441406 C 0 70.957031 6.714844 60.058594 16.691406 54.226562 C 14.636719 49.5 13.496094 44.28125 13.496094 38.796875 C 13.496094 17.375 30.890625 0.00390625 52.34375 0.00390625 C 64.9375 0.00390625 76.132812 5.996094 83.226562 15.273438 "></path>
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</svg>

Also found above code in Tech Shorts Git repo