  Classical T Tauri stars are surrounded by a circumstellar disk from which
they are accreting material. This process is essential in the formation of
Sun-like stars. Although often described with simple and static models, the
accretion process is inherently time variable. Our aim is to examine the
accretion process of the low-mass young stellar object CR Cha on a wide range
of timescales from minutes to a decade by analyzing both photometric and
spectroscopic observations from 2006, 2018, and 2019. We carried out period
analysis on the light curves of CR Cha from the TESS mission and the ASAS-SN
and the ASAS-3 databases. We studied the color variations of the system using
$I,J,H,K$-band photometry obtained contemporaneously with the TESS observing
window. We analyzed the amplitude, timescale, and the morphology of the
accretion tracers found in a series of high-resolution spectra obtained in 2006
with the AAT/UCLES, in 2018 with the HARPS, and in 2019 with the ESPRESSO and
the FEROS spectrographs. All photometric data reveal periodic variations
compatible with a 2.327 days rotational period, which is stable in the system
over decades. Moreover, the ASAS-SN and ASAS-3 data hint at a long-term
brightening by 0.2 mag, between 2001 and 2008, and of slightly less than 0.1
mag in the 2015 - 2018 period. The near-infrared color variations can be
explained by either changing accretion rate or changes in the inner disk
structure. Our results show that the amplitude of the variations in the
H$\alpha$ emission increases on timescales from hours to days/weeks, after
which it stays similar even when looking at decadal timescales. On the other
hand, we found significant morphological variations on yearly/decadal
timescales, indicating that the different physical mechanisms responsible for
the line profile changes, such as accretion or wind, are present to varying
degrees at different times.
