Not sure what the technical term is for this, but can something be done either within VAM to reduce the edges shown where the iris meets the sclera? Or would that have to be done in DAZ
Not realy Iris and sclera are not connect, you can try some iris universalmorph here https://www.patreon.com/c/vecterror/posts (just look for in the pin post for : If needed, you can find my standard files such as hair or assets here: Link). Also some iris texture have border that hide edge a little.