* If referring to lace fabric: You could use words like δαντέλα (dantela, borrowed from Italian and widely used for "lace") or a more descriptive phrase like λεπτό, διαφανές ύφασμα με σχέδια (leptom, diafanes yfasma me schedia - "thin, transparent fabric with patterns").
* If referring to something having a lace-like quality (e.g., lacey leaves): You might use words like λεπτό, δαντελωτό (leptom, danteloto - "thin, lacy") or phrases describing the delicate, intricate pattern.
Essentially, you need to describe the *characteristics* of "lacey" rather than finding a single word equivalent.