Roxy’s race is exclusively water-breathing. This does reduce the amount of information oxygen breathers have. There isn’t a real air-resonant name for them. The sonar-to-air translation comes out to ‘the Green Water People'.
The Green Water People use a high level of nonverbal communication - color changes in skin bear a lot of information. This is naturally lost when one stays in (or deals with) a monoform. They are generally known to be a subtle people. Direct questions are not actually rude among them, they’re just unusual. Direct answers, though, are a little. A too-detailed answer is a sign that (a) the speaker wants to deny the listener the challenge of working through the subtleties or (b) the speaker doesn’t think the listener is smart enough to figure things out.
Roxy’s people are all shapeshifters, although of variable skill. The least skilled can only change surface color and texture, and the most skilled can change their body chemistry and grow new limbs. Roxy’s something like 70th-80th percentile. She can adjust her biochemistry and physical structure to breathe air. She;s able to reinforce her physical structure enough to resist damage and to survive hard vacuum.
She's had a galactic tranlator bug put in.
The Green Water People are not generally teleporters. They have vestigial teleportation abilities (the spatial awareness and telekinesis, for example), but, evolutionarily speaking, they seems to have traded full teleportation for increased mental capacity some time ago. There are some creatures native to the planet that do still teleport. If a sentient inhabitant exhibits the ability, it’s rare enough to be considered a mutation, not a throwback. Roxy had her latent ability artificially activated. Why? You’d have to ask her. The unexpected edge has a lot to do with why she was able to stay free for long enough to rack up so many charges against her. The process also improved her secondary teleportation abilities somewhat. By her people’s standards, Roxy is either the low end of Meta, or the high end of Para.
Roxy’s body temperature is a little low compared to homo sapiens norms. She’s still warm blooded, but she’ll always be the coldest person in the room to IR. A doctor under the impression she was a normal human would probably be very concerned.
In her default form, she will pass for human at a cursory glance or in still photography. Her skin has an iridescent sheen to it and her hair is highly refractive (in still photography, it just looks like a little glare). She has gills across her torso/back, unless she deliberately conceals them. She does need them ‘open’ to breathe water.