Might replace Obsidian with Tangent on PC a̶n̶d̶ Z̶e̶t̶t̶e̶l̶ N̶o̶t̶e̶s̶ o̶n̶ A̶n̶d̶r̶o̶i̶d̶.

Tangent seems cool, but without the theming support of Obsidian.
Z̶e̶t̶t̶e̶l̶ N̶o̶t̶e̶s̶ i̶s̶ c̶o̶o̶l̶ t̶o̶o̶.

EDIT: Turns out Zettel Notes is non-free, just hosted on a 3rd party F-Droid repository.