makenmarketing

This plugin allows you to designate certain products in your WooCommerce store to have no price. Instead, it displays a configurable button for customers to request a quote directly via a chat app (like WhatsApp).
From the settings page, you can customize: 
* The WhatsApp phone number. 
* The button text and icon. 
* The predefined message the customer will send. 
* The button colors.

Quote via Chat Button

Replaces the "Add to Cart" button with a chat button for products without a price, with customization options.

impleCode

ndre

Add a price to any content type with a simple price field.
This plugin will add price box to selected post types (e.g. Posts, Pages).
You will be able to enable automatic display on fron-end or you can use [price_field] shortcode to place if in certain place.
<h4>Price Field Settings</h4>
You can select from 25 currencies available or set your custom currency symbol.
Select price format and price separators to match your needs.
<h4>Catalog X integration</h4>
Price Field is 100% compatible with Catalog X.

Price Field

Adds support for price field to posts, pages or other selected post types. Fully integrated with Catalog X.

Quote via Chat Button vs Price Field