They are mostly fairly old, because manufacturers have stopped making batteries removable (which is exactly why they’re legislating it). Some new though, and in fact Samsung’s current ultra-resilient rugged edition phones all have removable batteries: https://www.samsung.com/us/business/mobile/phones/galaxy-xcover-pro/. It’s clearly possible!
Here’s 106 phones with at least IPx6 (full immersion for 30 minutes) waterproofing and removable batteries: https://www.gsmarena.com/results.php3?sIPCerts=5,6&idBatRemovable=1
They are mostly fairly old, because manufacturers have stopped making batteries removable (which is exactly why they’re legislating it). Some new though, and in fact Samsung’s current ultra-resilient rugged edition phones all have removable batteries: https://www.samsung.com/us/business/mobile/phones/galaxy-xcover-pro/. It’s clearly possible!