Stadden won the 100 butterfly (53.99), 100 back (52.81), 100 free (50.65) and 100 IM (56.47) to finish with a total time of 4:38.61 across five events.
Ireland's Ellen Walshe will tackle the women's 100 fly and 200 IM on the opening night of the LEN U23 European Championships in Dublin, seeded second in both.