To find crystal wyverns you need to go to either the crystal arches or near the volcano. For nature you need to take the primal crystal from the back after tranking the wyvern then when it wakes feed it the crystal. For an ice wyvern you need to knock it out and Then run away, you can't take primal crystal from ice wyverns, running away won't make it agro then when it lands feed it primal crystal. Now you have two different types of wyvern in one place👍.
I don’t know if I’m stupid and it tells you this but I struggled with this for a bit and figured out that the wyverns of the same type Cant hurt each other which is something I figured out while shooting my blood wyverns blood at a blood wyvern for 15 minutes and it did nothing 😅