Alfred became her country’s first Olympic medallist after winning gold in Paris as Richardson took silver, with the St Lucian also claiming a silver in the 200m.
But American Richardson took victory in Switzerland in a strong field on Thursday, winning in 10.84secs.
Britain’s Dina Asher-Smith – who failed to reach that Olympic final – finished third, while compatriot Daryll Neita came seventh.
In the men’s 200m final, meanwhile, Botswana’s Olympic champion Letsile Tebogo continued his brilliant form to claim victory in 19.55secs as Americans Kenneth Bednarek and Erriyon Knighton finished second and third respectively.
The highly-anticipated men’s 1500m lived up to the expectation with a tight finish as Olympic bronze medallist Yared Nuguse beat the in-form Jakob Ingebrigtsen to claim victory.
American Nuguse finished one place ahead of Ingebrigtsen, as he did in Paris, while Olympic champion Cole Hocker came third.
Britain’s world champion Josh Kerr, who won Olympic silver, had to settle for fifth place.
In the women’s 800m, Britain’s Olympic 1500m bronze medallist Georgia Bell was second behind Kenya’s Mary Moraa, with GB’s Jemma Reekie in fourth.
Sweden’s Olympic champion Armand Duplantis continued his impressive all-round form with victory in the men’s pole vault.
Success for the Swede followed his victory in a 100m exhibition race against 400m hurdler Karsten Warholm on Wednesday.
The penultimate Diamond League meeting – before next week’s two-night final in Brussels – also saw Kenyan double Olympic champion Beatrice Chebet set a world leading time of 14mins 9.52secs in the women’s 5,000m.
Chebet was not the only gold medal winner from Paris to star on the night. Ukraine’s Olympic champion and world record holder Yaroslava Duplantis won the high jump, American Ryan Crouser took the shot put and his compatriot Grant Holloway won the 110m hurdles in an impressive 12.99secs
