Then do what I do when buying your next phone, find a custom ROM you like, check their “comparability” page, find devices that are fully compatible, preferably officially supported (community build usually work fine as well) and use that as a shopping list when browsing for phones.
The few options that exist (along with their negatives) can’t be installed on my phone. N20U is still pretty much locked down.
Then do what I do when buying your next phone, find a custom ROM you like, check their “comparability” page, find devices that are fully compatible, preferably officially supported (community build usually work fine as well) and use that as a shopping list when browsing for phones.