Is there anything like this for the Logitech keyboards (eg MX Keys Mini)? I want to remap some keys there too but don’t want to run Options+

Use kanata (github.com/jtroo/kanata). It's software remapping and works on any keyboard (including built-in laptop keyboards).

Great docs, incredible feature set (literally 50x the capabilities of any logitech first party remapper), and very lightweight.