Your example with "Beautifuls" doesn't work unfortunately. No native English speaker would use it.
... but it is possible to use "the beautiful" as a noun (requires the definite article), according to the OED. However there's no need to use a plural S form, since it can already be used as a plural. However, it doesn't work for a specific/small group of people like your example, but for beautiful people in general.
Here's the entry with a few of the more recent citations, but this usage dates back to at least 1542.
1.b. With the and plural agreement. Beautiful people as a class.
1721 She loves the poor equal with the rich; the deformed as well as the beautiful. T. M. Gibbs, translation of M. Le Roy de
Gomberville, Doctr. Morality 28/2
1794 The young Lady is said to be the most literary of the beautiful, and the most beautiful of the literatae. S. T. Coleridge,
Letter 26 September (1956) vol. I. 109
1839 The beautiful are forgiving. Corsair 6 April 58/1
1861 The beautiful do not always wed with the beautiful. Dublin University Magazine December 747/2
1962 The beautiful and the rich trembled in that elegant city. J. Daniels, Devil’ s Backbone xv. 214
2012 The young and the beautiful are not expected to conk out in this way. New York Review of Books 8 March 27/3
Source: Oxford English Dictionary, s.v. “beautiful, adj., n., & adv.”, July 2023. https://doi.org/10.1093/OED/6632057087. The link requires a login unfortunately.