what is the best things to convert for crafter level 4 materia?

[MN_14]

The level 55 DoH gear from Moghome works relatively well for grade iv conversions, but you're still looking at a 50%-70% conversion rate only. If you're gathering favor items, however, you might as well spirit bond them while you're at it.

[Vandril]

The level 55 DoH gear from Moghome works relatively well for grade iv conversions, but you're still looking at a 50%-70% conversion rate only. If you're gathering favor items, however, you might as well spirit bond them while you're at it.

This is exactly what I did while gathering favors. You don't need HQ items or to use skills for favor stuff, so I only kept on the gear that gave me substantial Gathering and replaced all my Perception/GP gear with HQ lvl 55 (not i55, level 55 requirement) crafting gear which I quickly crafted. So long as I was going to farm favors anyway, the Tier III/IV materia from spiritbonding the crafting gear was a nice bonus.