I'm actually holding all five HA legendaries from Dream Radar (two still have to be transferred to W2), so I am actually doing well for legendaries. :) Unless the Ho-oh is Kalos-originating, but I do not think there are legitimate Kalos-originating ones yet (hmm, I wonder if OR/AS will get them post-game...and the legendary dogs...). Too bad the 31 IVs don't apply to HA ability ones back then.
That said, if the Ho-oh has good IVs, that might be of interest. :) Can you get me stats on it? (Attack, Speed, HP, etc.) and the level/nature? If it's untrained, I can check it quickly.