@DanP76 

On occasion I have installed and internal AP (non weatherproof) inside a plastic weatherproof box with no issues.   This might be an option for you?

Even one of the RE605x extenders as you say, all you need into the box would be power and seal the connection with a gland

Example below..  just for reference, check the size before buying :)

https://www.amazon.co.uk/waterproof-adaptable-enclosure-electrics-connection/dp/B0151KNMB2

To extend your Wi-Fi coverage outdoors and maintain compatibility with your current setup, there are a few options you can consider. Here are some recommendations:

1. Outdoor Wi-Fi Range Extenders: While TP-Link's EAP650-Outdoor is primarily designed for business use, it is still possible to utilize it in a home setting. However, it may require additional configuration and setup compared to consumer-grade extenders. If you're comfortable with advanced settings and prefer a weatherproof extender, the EAP650-Outdoor could be a suitable choice. It's important to note that this model requires a wired Ethernet connection for power and data transmission.

2. Wi-Fi Mesh Systems: Another option is to consider a Wi-Fi mesh system that supports outdoor access points. TP-Link offers the Deco X60, a mesh system that includes both indoor and outdoor units. The outdoor units are weatherproof and can be mounted on the exterior wall to extend your Wi-Fi coverage outside. This solution offers seamless roaming and easy setup similar to your current indoor extenders.

3. Wireless Access Point with Powerline Adapter: If you prefer to avoid running Ethernet cables outside, you could use a combination of a wireless access point (WAP) and a powerline adapter. You can connect a weatherproof WAP, such as the TP-Link EAP225-Outdoor, to a powerline adapter installed indoors near a power outlet. The powerline adapter will transmit the network signal through your home's electrical wiring, allowing you to extend Wi-Fi outdoors without running Ethernet cables.

Remember to check the specifications and compatibility of the outdoor devices with your current Archer AX6000 router and RE605X extenders. Additionally, consider factors like range, weatherproofing, and installation requirements to determine the best solution for your specific needs.