Since the weapons in the SlashBlade Mod are differentiated via NBT data, this completely prevents proper recipe lookup. However, the CraftGuide mod for 1.7.10 can display them correctly. Could HEI consider adding support for this in the future? This would greatly benefit players and modpack authors :)

You can add items with specific NBT to ingredient sidebar using groovyscript
https://cleanroommc.com/groovy-script/mods/jei/ingredient#adding-entries