  Torsional Alfv\'en waves do not produce any intensity variation and are,
therefore, challenging to observe with imaging instruments. Previously,
Alfv\'en wave observations were reported throughout all the layers of the solar
atmosphere using spectral imaging. We present an observation of a torsional
Alfv\'en wave detected in an inverted y-shape structure observed with the
HRIEUV telescope of the EUI instrument onboard Solar Orbiter in its 174 \r{A}
channel. The feature consists of two footpoints connected through short loops
and a spine with a length of 30 Mm originating from one of the footpoints. In
the current work, we also make use of the simultaneous observations from two
other instruments onboard Solar Orbiter. The first one is PHI that is used to
derive the magnetic configuration of the observed feature. The second one is
SPICE that provided observations of intensity maps in different lines including
Ne VIII and C III lines. We also address the issues of the SPICE point spread
function and its influence on the Doppler maps via performed forward modeling
analysis. The difference movie shows clear signatures of propagating rotational
motions in the spine. Doppler maps obtained with SPICE show strong signal in
the spine region. Under the assumption that the recovered point spread function
is mostly correct, synthesized raster images confirm that this signal is
predominantly physical. We conclude that the presented observations are
compatible with an interpretation of either propagating torsional Alfv\'en
waves in a low coronal structure or untwisting of a flux rope. This is the
first time we see signatures of propagating torsional motion in corona as
observed by the three instruments onboard Solar Orbiter.
