Hi there.
As I’ve posted elsewhere regarding identifying shamisen, you need to know the dimensions of the neck’s width (at least near the tenjin), the overall instrument length from tip to tip (not accounting for the curve of the tenjin, just looking at the footprint), and the length and width of the body (not accounting for the bevel).
From these dimensions, it’s usually possible to figure out the intended genre.
Additional indicators include:
Shape of the neck near the body
Presence or absence of an adjustable sawari (en or azuma)
Relative size of the itomaki (extremely poor indicator, but there are trends)
Skinning type and dimensions
Accessories
Anyway
A quick glance at your link says: No, not a tsugaru