Battle ones, yes. Crafting/gathering no. Mutamix is usually involved. Haven't seen any new gear convert to tier 5 yet.

* Grade five materia for crafting and gathering classes will not be available at the release of patch 3.0. They are scheduled to be added at a later date. However, it will be possible to receive grade five crafting or gathering materia via materia transmutation by speaking with Mutamix.