Posing is where a character stops being a mesh and starts being a performer. The AI-era twist is that the reference half of the job got dramatically cheaper - skeleton extraction from a photo now takes seconds - while the craft half stayed exactly as demanding. Know which half you are buying automation for, and the tools sort themselves.
Job one: photo to pose reference
The modern reference loop: find or shoot the stance you want, run it through pose estimation to get a clean 2D skeleton, and use that overlay as your target while you pose the 3D rig by hand. It sounds like extra steps and reads as a superpower - matching a cover photo, a client's sketch or a sports frame stops being guesswork. The estimation tools are fast and free; the judgment call is the matching, and matching is done by you, on the rig, one joint at a time.
Job two: exploring poses quickly
Sometimes the blocker is not accuracy but decision fatigue - you need twelve candidate poses for a client before lunch. Pose-library addons and online posing toys excel here: pose the skeleton fast, screenshot the options, pick two to refine in Blender. Speed beats fidelity at this stage, because the winner gets rebuilt properly anyway. The habit that makes this scale: save every keeper into Blender's Asset Browser as a pose asset, named and thumbnailed. Six months later that library is the most valuable rigging work you own.
Job three: landing the pose on your rig
A pose from a library or an external skeleton does not walk itself onto your character. The route is retargeting: map the donor skeleton's bones to yours - spine to spine, upper arm to upper arm - paste the pose, then fix what the mapping got wrong. Three repairs carry most of the value:
Shoulders and clavicles. The first place bad retargets show: arms that pierce the torso or float. Give the clavicle half the rotation the donor gave it and watch the silhouette heal.
Wrist roll. Donor skeletons disagree about which way is up on the forearm. A flipped wrist ruins a grip pose; the fix is a 180-degree roll at the wrist once the arm reads correctly.
Ground contact. Feet slide on the floor plane after retargeting - check the contact foot first, plant it, then adjust hips. Gravity is the one client that never signs off on approximations.
When the character itself is generated
AI-generated characters arrive in a T-pose or A-pose with approximate weights, which makes them promising and slightly cursed as posing targets. Two habits pay: test the generated rig with three extreme poses before falling in love with it - the shoulders will tell you if the weights are salvageable - and do the first weight fixes immediately, because every pose after inherits them. Detailed on the rigging guide; the short version here is that a pose generator multiplies whatever rig quality you feed it, for better and for worse.