Seaborn's FacetGrid has a margin_titles
kwarg, and its effect is shown in the documentation e.g.
How do I similarly add margin titles when using Seaborn's relplot?
I am not sure how you want to use it, but this can be given in a dict in the facet_kws argument.
import seaborn as sns
tips = sns.load_dataset("tips")
sns.relplot(
data=tips,
x="total_bill",
y="tip",
hue="time",
col="day",
row="smoker",
facet_kws={"margin_titles": True}
)