In September 2018 cruised from Bremerhaven to Palma Mallorca on Tui ship Mein Schiff 3. The facilities were spacious and mixed. Rest lounges inside the facility and immediately outside on a sun deck provided a comfortable private retreat.
Naturally Germans appear to hold less inhibition regarding mixed facilities but you can wear your swimmers in need.
Change rooms were not mixed, although internal showers in the facility were. Probably one of the better facilities that I have used with staff member assisting in the sauna temperature buildup, but to levels I couldn't comfortably manage.