Thank you many opinions in this topic! 
Thanks to your help and information input, I was able to decide on a design for my Headcanon Suletu!
・Krakua’s Suletu having a scaly half depends on whether the scales on Kongu’s were a result of it being organic or not.
・The nature of the masks has to do with how they got them (Kongu’s one being buried for quite some time).
・Kongu’s one is “true shape”. (It’s unclear if this is a response to Krakua’s Hau-Suletu or if it is literally the regular shape as it is.)
・All(regular) Suletu’s have reptilian growth like Kongu’s.
・Inorganic Inika masks look pretty much the same as their organic counterparts.
・Inorganic Inika masks look somewhat different from their organic counterparts.
… I created this in response to a series of answers that included these contradictions, thinking that everything would be as valid as possible, and tried as much as possible to there will not be happened unmatch discrepancy in appearance when Krakua wears this . 
When I was thinking about the design, I picked up a piece of Kongu’s Suletu and looked at it, thinking about it.
However, upon closer inspection, I noticed that the organic tissue was protruding from the edges of the eye holes (on both sides).
There was some controversy about Suletu’s scales, but I interpreted this as “Regular shape also has scales, but they are usually hidden under a “mask” except for the chin” or “Red Star’s lightning repaired the damaged area with organic tissue”.
I thought this would explain Greg’s seemingly contradictory comments about “Kongu’s Suletu is true shape”, “Krakua’s Suletu having a scaly half depends on whether the scales on Kongu’s were a result of it being organic or not”, and “Regular Suletu has scale part”.
(I thought it would be unnatural to have the structure built into the inside of the mask, since the shape of the mask is just a sign to identify its abilities, but this was the best solution I could come up with.
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(3D printed-Suletu before be processing(Polishing, Adding scale, and painting)
(Inspirated and based on @MaskMaker / KhingK’s symmetry Suletu and @Tarkur 's! Thank you!) 
