The Skyreach 4 Mini is a HTPC case that does not support any internal PSU. As the 2700X does not have integrated graphics, you will have to add a GPU. But as external PSU aren't available with more than about 200W, this GPU had to be extremely low powered... Such a card in combination with a 2700X wouldn't make much sense. In addition, the 4 Mini just supports 45mm of CPU cooler clearance, which is absolutely nothing for a 105W TDP chip like the 2700X, no chance to cool it properly.
The Dan A4 can handle up to SFX-L PSUs which are available up to 800W, so you have much more power to fit an GPU with adequate performance. If you get your hands on a 92mm AIO, you have a good chance to cool the 2700X, but it still won't be ideal.
My suggestion would be to go for the NCase M1 with a 240mm AIO for your CPU.