Sergey

This plugin gives you option to choose which payment gateways will be disabled when certain shipping method selected. 
Say, you can disable Cash on Delivery for Flat rate. 
Or disable Paypal for Local Pickup.
This WooCommerce addon is compatible with: 
* WooCommerce 3.5.2

WooCommerce – Shippings Payments Restrictions

Disable payment gateways for certain shipping method.

agraddy

The WooCommerce Fake Pay plugin is a payment gateway for WooCommerce that allows admin users to checkout without having to enter any payment information. Simply choose the “Fake Pay” payment option on checkout and it will process the order as if you had paid with a real payment gateway.
This plugin is useful for testing a WooCommerce checkout flow on a production site where real users are making payments with real payment gateways. The real users will not see the Fake Pay option but logged in admin users will be able to use the Fake Pay option.

Fake Pay For WooCommerce

Great little plugin for debugging, thanks!

Great for debugging

Thanks for making this plugin, it's perfect for testing. I'm currently using it with WordPress 5.3.2 and WooCommerce 3.9.2 

Perfect

A simple pass-through WooCommerce payment gateway that can be used for testing orders with an admin account.

WooCommerce – Shippings Payments Restrictions vs Fake Pay For WooCommerce