There's a closed pull request on the void-packages repository

base-files: modify kernel listing in vkpurge
https://github.com/void-linux/void-packages/pull/24310

Description:
By default, kernel listing is not done by version. For example :

    4.19.131_1
    5.4.18_1
    5.4.50_1
    5.4.5_1
    5.4.9_1
    5.4.11_1

Using 'version-sort' option, it shows older versions before recent versions :

    4.19.131_1
    5.4.5_1
    5.4.9_1
    5.4.11_1
    5.4.18_1
    5.4.50_1