We had senior "wills," where the seniors would give a little something to someone else in the chapter. Sometimes it was literally something from their room at the house that they didn't want to take with them, sometimes it was advice or a heartfelt thank you...basically, whatever the senior wanted to "leave" to a non-graduating sister, with an accompanying speech. Sometimes seniors would leave stuff to more than one person. You could also have nongraduating actives create sendoff messages for the seniors, so there is reciprocity and direct recognition of the seniors.
This could be easily modified for online. Even some physical items could be mailed after the ceremony. The name could also be changed to something like "Senior Legacies" or something like that, if "will" sounds too morbid given the circumstances.
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@>----'---,---- Alpha Omicron Pi -----Phi Beta Kappa ------
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