As it mentioned in CROCHET OR KNIT SIMPLE PRESSURE SENSOR post, the properties of the conductive yarn is sensitive to pressure or stretch. So, if you knit or crochet the conductive yarn to shape of finger, it can be a finger sensor like Sensitive Finger Tips project, but with crochet material instead of fabrics.

These example sensors are made with Schoeller conductive yarn (Nm 10/3 80% Polyurethane, 20% Inox steel fibre) and normal wool yarn.
The sensor ranges from around 1k ohm (not touching) to 500 ohm (touching), and around 1k ohm (not bending) to 200 ohm (bending). This also depends how tight the finger sensors are when worn since by wearing it, it stretches the conducive yarn causing initial decrease in resistance.

Finger tip sensor type 1:

Finger tip sensor type 2:

Finger bend sensor: