[NTG-context] How to define a {\bf}-compatible fake-bold switcher?

Dear List, I'm using a weirdfont that does not have a pre-defined bold variant but still want to emboldening short extracts of text occasionally, so I've defined \defineeffect[thicker][alternative=both,rulethickness=0.3pt] \define\fakebf{\effect[thicker]} but in situations like {\fakebf \definedfont[weridfont] 1 2 3 \definedfont[modern]4 5 6} the "4 5 6" is faked bold even if latinmodern has a proper bold font. Could anyone help me define a {\bf}-aware version of \fakebf which can render the "4 5 6" in the example above in latinmodern's bold? Thanks in advance. Best, Sylvain