FT8 would be pointless. FT8 uses SSB which this can't do. Doing FT8 on FM is a waste of bandwidth and low-signal. FT8 is usually done on HF since that has long-distance propagation and it is important to pick out tiny signals. People do FT8 on VHF but they use radios with SSB.
The radio probably doesn't have the processing power for FT8. A Raspberry Pi 3 was struggling for me. Also, a big part of FT8 is choosing what to send and who to respond to, need a good display for that.
It seems that there is a firmware doing SSB (I don't understand if it's real SSB or something emulated).
Anyway, the radio chip of UV-K5 is able to manage distinct I-Q signal, so it just a matter of implementing SSB via software.
SSB requires more sophisticated frontend than FM because the channel is smaller and reuqires less noise. There are HF radios that use a simple signal generator, but then need a complicated frontend to be able to received anything. The cheap SDR HF radios are $500 when SDR VHF handhelds are cheap like this one.
The radio probably doesn't have the processing power for FT8. A Raspberry Pi 3 was struggling for me. Also, a big part of FT8 is choosing what to send and who to respond to, need a good display for that.