I upgraded my project from KL27Z64 to K32L2A, and flashing from PC (over USB) with CLI blhost is the same. I also have new MCU-LINK, but for me (instead of breakpoint debugging I am using fast 4Mbps UART logging) CLI blhost is simple better.
If I remember right, K32L2B is with the same ROM USB loader as K32L2A, but you can check this in device datasheet.