Yes you can, but be careful with the cables and the cable routing.
The arm is extremely sluggish and due to the high mass of the arm + monitor I managed to rip my display port cable out of the DP connector. Luckily I had a replacement and the Poet wasn't damaged...

The Xantron monitor mount for XL monitors supports monitors up to a size of 57 inches and has a maximum payload of 27 kg. To ensure that it is compatible with the Samsung Odyssey Neo G9, you should check whether the monitor has the VESA connection sizes of 100 x 100 mm, 100 x 200 mm, 200 x 100 mm, 200 x 200 mm or 75 x 75 mm and whether it is within the weight limit. The Samsung Odyssey Neo G9 has a size of 49 inches and weighs about 13 kg, which is within the specifications of the mount. However, it is advisable to check the exact VESA dimensions of the monitor to ensure an optimal fit.