Thri-kreen is another race that is problematic to convert, because quite frankly they were overpowered in 2e. Defining traits are: alien mindset, non-humanoid, multi-armed, thick chitin exoskeleton, less need of water. They will either need to be reduced in power, or be given a level adjustment. One solution might be racial levels, as in Arcana Unearthed. That would also explain the differences between a starting PC thri-kreen and a “monster” thri-kreen – the “monster” is simply one that only has racial levels. Worth thinking about.