So my impression now is:
For paste highlighted
Initial clipboard text:
some text to highlight
KM-generated clipboard text:
%%tana%%
- ==some text to highlight==
For paste struck
Initial clipboard text:
some text to strike through
KM-generated clipboard text:
%%tana%%
- ~~some text to strike through~~
For copy URL from browser to paste in Tana
You could use the Keyboard Maestro tokens:
to assemble your
%%tana%%
- [title](URL)
for pasting.