In case anyone's looking for better clues I'll post my /etc/wscons.conf for reference. This doesn't enable latin2 (but instead enables 80x50 screens), but that can be done by commenting out a couple of lines, and uncommenting a couple of other lines.
# $NetBSD: wscons.conf,v 1.19 2011/07/22 19:06:23 christos Exp $
#
# workstation console configuration
# fonts to load
#
# Note that not all wsdisplay(4) driver implementations are capable of
# loading fonts.
#
# Note: You must uncomment the 'font ibm - 8' line to get a useful font for
# any 50 line screens on vga(4) screens, and otherwise you may get what
# appears to be a black-on-black display.
#
# - 50-line screens need fonts with a height of 8 pixels
# - 40-line screens need fonts with a height of 10 pixels.
#
# name width height enc file
font ibm - 8 ibm /usr/share/wscons/fonts/vt220l.808
font ibm10 - 10 ibm /usr/share/wscons/fonts/vt220l.810
font ibm16 - 16 ibm /usr/share/wscons/fonts/vt220l.816
#
# You could use the '80x50bf" screen type and also load the "pcvt08" font into
# the upper half of the extended character set, but doing so limits the number
# of colours to 8 instead of the standard 16.
#
# Note: the upper half of the "pcvt" encoded fonts are only useful
# with the "*bf" screen types of the "vga" driver. The kernel must be
# compiled with the option "WSCONS_SUPPORT_PCVTFONTS" turned on. See
# vga(4) and wsfontload(8).
#
#font pcvt - - pcvt /usr/share/wscons/fonts/vt220h.816
#font pcvt - 8 pcvt /usr/share/wscons/fonts/vt220h.808
# Font for central european languages (ISO 8859-2).
# Uncomment to load. Needs to be explicitly enabled (see below).
#font latin2 - 16 iso /usr/share/wscons/fonts/latin2.816
# screens to create
#
# Available emulations depend on which wscons(4) WSEMUL_* kernel
# options have been used. "vt100", "sun" and "dumb" are the ones
# currently supported in the driver, and which are available by
# default depends on which architcture is in use.
#
# Note the "vt100" emulation should be used with the "TERM=wsvt25" or
# "TERM=wsvt25m", especially for applications using NetBSD curses(3).
#
# See ega(4), vga(4), etc. for supported screen types.
#
# Note: You must uncomment the 'font ibm' line above to get a useful
# font for any 50 line screens.
#
# index type emul
# Screen 0 is already configured as console in most cases.
# Uncomment if a serial console is used.
screen 0 80x50 vt100
screen 1 80x50 vt100
screen 2 80x50 vt100
screen 3 80x50 vt100
screen 4 80x50 vt100
screen 5 80x50 vt100
# leave the last active one as 80x25 just in case the font load fails
screen 6 80x25 vt100
# Screen 7 is for the X11 server started by xdm (on vt08) to attach to
screen 7 - -
# Keyboard and mux are automatically configured if they are the console.
# Uncomment the next two lines if a serial console is used.
#keyboard auto
#mux
# Select a kernel builtin keyboard map by uncommenting the following line and
# altering the country code to your requirements
#
# (choose from user, us, uk, be, cz, dk, nl, fi, fr, de, gr, hu, it, jp, no,
# pl, pt, ru, es, sv, sf, sg, ua)
#
# See wsconsctl(8), pckbd(4), ukbd(4) etc. for more details.
#
#encoding sv
#
# N.B.: you will want to disable swapctrlcaps if using VirtualBox on
# a host which already has had the swapping done on it!
#
# Also N.B.: the virtual console swapping may still use the "real" Ctrl-L key
#
encoding us.swapctrlcaps
# Redefine individual keys from a file containing "keysym" and/or "keycode"
# entries.
#
# See wsconsctl(8) and /usr/share/wscons/keymaps for more details.
#
#mapfile /usr/share/wscons/keymaps/pckbd.sv.svascii
# Set arbitrary wscons variable using specified control device
# ctldev var value
#setvar ttyE0 font ibm
#setvar ttyE1 font ibm
# Uncomment for ISO 8859-2 support
#setvar ttyE0 font latin2
#setvar ttyE1 font latin2
#setvar ttyE2 font latin2
#setvar ttyE3 font latin2
# Change keyboard repeat speed to faster settings.
#setvar wskbd repeat.del1 250
#setvar wskbd repeat.deln 30
