ThemesWP

Using Ultimate Custom ScrollBar for customize scrollbars, you get a very elegant and unique site. Consistent scroll behavior for every device. You can change scrollbar size, colors, animation, position from this settings page.
Plugin Features
<ul>
<li>Simple installation & activation</li>
<li>Supported touch devices.</li>
<li>Unlimited colors.</li>
<li>Lightweight.</li>
<li>Enable/Disable Option.</li>
<li>Easy Option Panel.</li>
<li>All browser supported</li>
</ul>
Free Options
<ul>
<li>Enable/Disable ScrollBar : You can enable or disable scrollbar using this option.</li>
<li>Cursor Width : You can increase or decrease cursor width using this option.</li>
<li>Rail Background Color : You can change rail background color from this color picker.</li>
<li>Cursor Color : You can change cursor color from this color picker.</li>
<li>Auto Hide Mode : You can select scrollbar auto hide mode from this selectbox.</li>
<li>Included all free options.</li>
<li>Cursor Border : You can control cursor border using this option.</li>
<li>Cursor Border Radius : You can control cursor border radius using this option.</li>
<li>Scroll Speed : You can control scroll speed using this option.</li>
<li>Mouse Scroll Step : You can control mouse scroll step using this option.</li>
<li>Emulate Touch : Enable cursor-drag scrolling like touch devices in desktop computer.</li>
<li>Minimum Cursor Height : You can set the minimum cursor height.</li>
<li>Bounce Scroll : Enable scroll bouncing at the end of content as mobile-like.</li>
<li>Horizrail Enabled : You can control horizontal scroll.</li>
<li>Rail Align : You can control alignment of vertical rail.</li>
<li>Rail Valign : You can control alignment of horizontal rail.</li>
<li>Enable Mousewheel : You can control Mousewheel using this option.</li>
<li>Enable Keyboard : You can enable or disable keyboard events using this option.</li>
<li>Hide Cursor Delay : You can set the delay in microseconds to fading out scrollbars.</li>
<li>Enable Scroll On Selection : You can enable auto-scrolling of content when selection text.</li>
<li>Cursor Drag Speed : You can set speed of selection when dragged with cursor.</li>
</ul>

Ultimate Custom ScrollBar

Using Ultimate Custom ScrollBar for customize scrollbars, you get a very elegant and unique site. Consistent scroll behavior for every device.

Freemius

WP Mighty

<a href="https://wpmighty.com/wordpress-plugins/scrollbar-customizer" rel="nofollow ugc">Scrollbar Customizer</a> is an advanced WordPress plugin that let you easily customize and change the design and control of the scrollbar in your website.
<h3>The Key Features of Scrollbar Customizer</h3>
⭐ Customize dragger height 
⭐ Customize bar width and side space 
⭐ Customize bar background color 
⭐ Customize dragger color 
⭐ Change bar border radius 
⭐ Compatible with all page builders 
⭐ Compatible with all WordPress themes 
⭐ Gutenberg compatible 
⭐ Include pot file for translation 
⭐ Compatible with last WordPress version 
⭐ Lightweight and fast with no jQuery 
⭐ Compatible with all modern browsers
<h3>Pro version Features</h3>
⭐ Dark mode theme support 
⭐ Gradient dragger support 
⭐ Change wheel speed 
⭐ Size Animation on hover
<a href="https://wpmighty.com/wordpress-plugins/scrollbar-customizer" rel="nofollow ugc">Get pro version now</a>

Scrollbar Customizer

Easily customize and change the design and control of the scrollbar in your website.

Ultimate Custom ScrollBar vs Scrollbar Customizer