People are right. Try not to get to hung up on the box and consider more the management. The Warre hive can be used with the Warre management process (is designed for it) but it can be managed in much the same way as conventional hive too. Using half frames or frames, ans supering.
Equally, your nationals can be managed using Warre style management.
Steps:
Use two dummy boards to help narrow the space and reduce the weight.
Go foundationless, use a thin starters strip in the top of the frame.
Provide the bees with two national broods to live.
Nadir (place underneath) boxes through spring allowing the bees to grow down.
If they fill the boxes remove the boxes from the top in the autumn leaving two to over winter.
The biggest issue is going to be the weight. Warres hives are usually made with a handle on each side and routinely people will use a lift in order to lift all the boxes in one go to nadir.
See how it goes with using Warre management for your nationals and if it goes well and you want to go to Warre hives.
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