Hello, I tested this and you should read description more carefully!

Although the wording is inaccurate (it should say field), it indeed works. It buffs Earth attribute ninjas outside your lineup, just as Sasuke's Y/Y+1/Y+2 barrier does to Lightning attribute ninjas.

edit:

His +2 barrier says he will buff only units in your lineup though. I don't have access to Yamato with +2 breakthrough at the moment, so can someone confirm/deny that it will buff only units in your lineup?...

Does +2 mystery affect only lineup or entire field?