Hey, I’ve also been looking for a proper Evernote replacement over the last three years.
Closest actual system to Evernote I’ve used is Zim Wiki, which includes most all features you want besides the web clipper. Zim is extremely well designed + makes it easy to link files of any size. Supposedly you can host it via PicoCMS application for Nextcloud, but I’m still testing it. Zim even includes it’s own little html server for hosting content… it is amazing, and in some ways kicks the pants off Evernote. No built-in web clipper that I’m aware of.
Joplin does the best job of exactly rendering your many thousands of exported Evernote files, but it is still missing the ability to easily export attachments, location data, and other features. For now you have to browse to the resources directory and search for the associated file id number in order to export an attachment such as a picture… no download button, etc.
Tagspaces web clipper does a good job of saving data, but I see it is not yet compatible with latest Firefox Quantum. Should work fine on Google Chrome. Not sure if you can use it without Tagspaces webdav client, which is currently in development for functional connectivity to Nextcloud.. Tagspaces application has a lot of useful features, some notably superior to Nextcloud, but also needs more time to develop.
Haven’t tested Laverna yet, but I know a lot of people are recommending it as a self-hosted solution with end-to-end encryption.
WebtoPDF is an open source add-on that will convert web pages to PDF. I’ve heard good things about it as a stand-alone tool. Looks like it is also not compatible with Firefox Quantum.
Web Scrapbook is the current current successor to the old open source Scrapbook X, and also designed to transform websites into HTML files.
Web to SE is the best web clipper I can find for Firefox Quantum, saving web pages as “enhanced html”