It would be nice to reclaim old symbols. But that's not feasible as long as they're people who remember their misuse and their children, who heard those appalling stories from their parents.
However, I honestly never met with any issue wearing my Mjolnir openly. So far, in Europe.
In which countries did you experience any backlash to wearing Mjolnirs?
Obsidian is great; all the files are readable anywhere (easy to migrate out if needed) in a clear, readable directory structure, copying the structure you see in Obsidian itself. For something like $8/m, you can have their official sync tooling and have it on any devices at the same time, but there are also free options for synchronisation, which require a little work. You can probably find tools that would migrate your content from Anvil to Obsidian, but also the other way around. There are generally plugins for almost everything; however, there are too many plugins you can use; it's easy to get lost there. Also, as with many other plugin marketplaces, there is no security vetting on the plugins, so you need to be careful.