A phantom blade begins play with an ectoplasmic sentient weapon known as a phantom weapon whose weapon type is chosen by the phantom blade. The weapon type must be one with which the phantom blade is proficient. A phantom weapon functions similarly to the black blade of the bladebound magus archetype (Pathfinder RPG Ultimate Magic 47) except as noted on the Phantom Weapon Progression table on page 6 and in the descriptions below. A phantom blade with this class feature can’t have a phantom of any kind, even from another class.
This replaces phantom, phantom recall, spiritual bond, and dual bond.
Does the phantom weapon get skills as a normal phantom,
A phantom can assign skill ranks to any skills, but it must possess the appropriate appendage to use some skills. Phantoms with Intelligence scores above the base value modify these totals as normal (a phantom gains a number of skill ranks equal to 2 + its Intelligence modifier per Hit Die). A phantom can’t have more ranks in a skill than it has Hit Dice. Phantom skill ranks are set once chosen.
or does it get skills as per the blackblade?
Languages and Skills: A black blade starts with Common as a language. As the black blade increases in Intelligence, it manifests knowledge of languages and arcane lore. Upon reaching an Intelligence of 12, it gains a bonus language of the GM’s choice, and gains 1 rank in Knowledge (arcana). Each time the sword gains a bonus to Intelligence, it gains another language and another rank in Knowledge (arcana).
I believe RAW supports the latter, but I like to double check.
Phantom Blade replaces your Phantom, and therefore uses the Blackblade skills since Phantom Skills are a part of the Phantom class feature (or, really, phantom stat block).