FlareSeal® Model MSP-0408 Leak Free SAE Flare Connections - Refrigerant Leaks Refrigeration, HVAC, Ductless, Schrader Valve or Mini Split Applications (1/4", Mini Split Pack - (2) 1/4" and (2) 1/2")

You don't want low spot oil can collect there. They are designed to have the ODU lower then the IDU. You can get longer line set and re-flare the ends. Just get a good flare tool I use Hilmore. If you can't pressure test with nitrogen then get flare seals and use nylog only on the flare not the threads. Use a torque wrench with a adaptor at 90 degrees. You can find videos on youtube. That is the cheapest way to adapt a 3/8" torque wrench. Actual HVAC torque wrench is $200. https://a.co/d/0bxsrI7g < example of Flareseal.