yes we can confirm that part EEU-FC1V681S is an alternative for part EEUFC1V681B.
Not only the height differs: 15,00mm for EEU-FC1V681S vs of EEU-FC1V681B but also the impedance, pitch distance and some more parameters need to be checked in the below comparison chart:
Kondensatoren | Aluminium-Elektrolytkondensatoren | DigiKey
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