Well, that didn't take long.
There is a first experimental native-code port of Forth -- Mecrisp Forth, to be exact -- to the RISC-V (RV32IM), as the German Forth group Forth e.V. announced on Tuesday (in German). You can find it on the download page as Mecrisp Quintus.
One note of warning: There is this line HIC SUNT DRACONES in the README, which obviously translates to "dragons might get hiccups". So if you're a dragon, be careful!