@Xaron so glad you like TL. Regarding licensing of the data from ESRI in TerraLand, refer to this post:
TerraLand 2 – High Quality Photo-Realistic Terrains from Real-World GIS Data page-4#post-2798301
As far as we know, this is the imagery which is mostly under licensing regulations rather than elevation data if you are using them heavily in commercial projects but as stated through the information shared, there is no hard restrictions for using them regularly.