Yes, home and away friendlies were part of the deal with Legia Warsaw for Deyna. The home one was delayed from the original planned date and eventually played as a pre-season match in August 1980:
https://www.citytilidie.com/latest/legia-warsaw-home-friendly-198081/
We were battered, really outclassed. At 5-0 down, the Kippax started cheering on Legia, doing the 'ole' thing as they knocked the ball around and booing if City got it back again. Kevin Reeves scored our consolation near the end against a backdrop of chants of, "We want six! We want six!" The exaggeratedly wild celebrations after Reeves's strike were intended as an absolute piss-take.
You could tell from that display we were in big trouble for the start of the forthcoming season, and we were beaten easily at Southampton four days later before losing 4-0 at home to newly promoted Sunderland the following midweek. I remember the Legia match quite clearly because it was the first time I'd seen the City crowd turn on the team like that.