The 2018 Easton Beast X -10 Senior League Baseball Bat: SL18BX10 and the 2018 Marucci Hex Alloy 2 -10 Senior League Baseball Bat: MSBHA2X10 are both quality bats and have similar balanced swing weights. The big difference will be the alloy used to make the bat. The Beast X uses ATAC Alloy which is considered to be extremely strong and powerful. The Hex Alloy 2 uses AZ105 Alloy which allows for thinner barrel walls and better performance. This means the ball might pop off the barrel with more explosiveness.
The difference is in the material. The 2018 Easton Beast X -10 Senior League Baseball Bat (SL18BX10) is a one piece allow where the Voodoo is a hybrid with the barrel being alloy and the handle being composite. This allows for vibration reduction. The end cap on the Voodoo is also more advanced allowing for better weight distribution making the Voodoo more balanced. The end cap also allows for better vibration reduction. If the weight and vibration doesn't bother you, the SL18BX10 is the way to go. However, if the weight and sting will effect you, i recommend the Voodoo.
Since the 2018 season is still a little bit of a ways off, we haven't been able to receive a significant amount of reviews on the 2018 bats just yet. However, I imagine that this 2018 Easton Beast X -10 Senior League Baseball Bat (SL18BX10) will receive excellent reviews once springtime comes and more people get the bat in their hands.