If I understand correctly, you would want to start by melting your dataframe because it is currently in wide format and Seaborn prefers long or tidy format.
Then you can use sns.catplot() so that you have three plots, instead of one. From the docs:
Use catplot() to combine a boxplot() and a FacetGrid. This allows
grouping within additional categorical variables. Using catplot() is
safer than using FacetGrid directly, as it ensures synchronization of
variable order across facets:
### Make dummy dataframe
id = np.arange(1,10,1)
np.random.seed(0)
CCL = list(np.random.randint(5, size=len(id)))
CMCT = list(np.random.randint(8, size=len(id)))
CD = list(np.random.randint(5, size=len(id)))
CPAA = list(np.random.randint(9, size=len(id)))
CSC = list(np.random.randint(12, size=len(id)))
SIE = list(np.random.randint(5, size=len(id)))
CEC = list(np.random.randint(7, size=len(id)))
labels = list(np.random.randint(3, size=len(id)))
df = pd.DataFrame(list(zip(id, CCL, CMCT, CD, CPAA, CSC, SIE, CEC, labels)),
columns =['id', 'CCL', 'CMCT', 'CD', 'CPAA', 'CSC', 'SIE', 'CEC', 'labels']
)
print(df)

### Now melt and plot
df_melt = pd.melt(df, id_vars=['id', 'labels'],
value_vars=['CCL', 'CMCT', 'CD', 'CPAA', 'CSC', 'SIE', 'CEC']
)
print(df_melt)
sns.catplot(data=df_melt, x='value', y='variable', col='labels', kind='box')
plt.show()
