Orbi Wi-Fi 6 (RBR750) mesh to outbuilding

plemans is totally correct.  Search Amazon for "point to point wireless bridge".

The "A" solution for an outbuilding is a physical Ethernet cable. (a) no moving or electronic parts to fail, (b) nothing to configure, and (c) offers wonderful speed.  Alas, the maximum distance for Ethernet is about 100 meters (300 feet) and this distance of 450 ft. is too far.  Also installing a physical cable, including penetrating buildings, can be overwhelming.

Wireless bridges are rated in terms of kilometers, which means that people often find they can mount the antennas inside both buildings and still achieve wonder performance over shorter distances.  If not, they are often powered through the Ethernet cable (Power over Ethernet - PoE) and getting a cable through the wall to an outside mount is not all that difficult.

Another factor to consider is what to put at the remote site.  The benefit of placing another Orbi satellite out there is that mobile devices (phones, tablets) may roam seamlessly between the two locations.  Although, at 450 ft. you might find that mobile devices drop WiFi completely somewhere along the path and simply connect to the WiFi they find at the other location.  (not technically "roaming".  more like when you drive away and come home hours later.)  In that case, any WiFi access point of any brand might be less costly than the $200 a used RBS750 sells for.

Wireless bridges are not able to provide the same raw speed that an Ethernet connection or a 5G WiFi backhaul that is 30 ft. from the router can.  It is important to read the specifications carefully and look at the customer reviews.  The least expensive products are from companies most of us have never heard of.  Mainstream companies such as Ubiquiti and TP-Link offer a wide range of products with different capabilities (and at different price points).

Good Luck!