The miner already has both argon2i code and sha512 code but there are some issues.

First the Argon2i version is currently untested although I see no reason it shounldn't work.
Second I need Aronium's Argon2i parameters. They can be obtained from a spec or sample
code.

Additionally there are differences in the implementations or Argon2 and Sha512 that need to be
resolved. Argon2 uses linear vectors while sha512 uses parallel vectors. Without going into technical
detail, this complicates the implementation of an algo that uses both.

With all that it should be doable.