There actually ARE products out there that have both. E.g. “STREAM DESKTOP RECHARGE” bundle from Cherry can do both.
(Disclaimer: I work for Cherry, so I just happen tp know that product. But I am certain that there are other similar products from other brands as well.)
You could look into using 3rd party clients to view Lemmy. They often enhance the default behavior with additional features. E.g. Voyager (the one I’m using) has a “keyword filter”.