If we look up the frame at [0:20] in this Sea Horizon Character Introduction Trailer Youtube Video, we can see Dylan fight and stand on the same line with what appears to be a goblin. A goblin is a type of monster typically found as enemies in many video games, they are known to be small in stature (although some of them may evolve to become big, those are not really your typical goblin), they measure somewhere in between 3 to 4 feet in height.
By observing the visual height difference between Dylan and the goblin, we create an assumption that the goblin should stand at the maximum possible height of 4 feet since if the goblin is smaller than that, Dylan would receive a height lower than 5’2. 5 feet and 2 inches as a height for an athletic warrior doesn’t seem to be so plausible so therefore we cannot create a proper height correlation if the goblin’s height were to fall below 4 ft.
At 4 feet, the goblin stands on the same height line as Dylan’s chest, that is about 70% of Dylan’s maximum height. By using Hikaku Sitatter Height Comparison Tool, we were able to figure out that if Dylan’s chest height is at 4ft relative to the maximum height of the goblin, it would dictate that Dylan’s maximum height should be somewhere around 5’5.
When we look at some images of Dylan and other characters on Google Search Image, we can see that 5 ft 5in as height for Dylan sounds very plausible.