Filet Lace most often refers to a form of lace which has an open grid with filled square of the grid making a pattern. A version of crocheted lace which look similar to the traditional lace is the kind most commonly found today. It is called Filet Crochet.
There are tons of filet crochet patterns out there, both on the Internet and in books, with graphed patterns which can easily be converted to needlepoint.
Traditionally this lace is done in white or off-white, but recently I have seen it done in colors as well. This creates additional possibilities for needlepoint.
There are a couple of approaches to converting filet crochet to needlepoint, one using an open canvas and one using different stitches to make the pattern with a completely stitched pattern.
The open method is pictured above in a partially stitched design taken from an Internet pattern of a swan. The effect of the lace comes from using colored canvas and cream threads. The grid is made using straight stitches and the filled squares are made using Mosaic Stitches.
The method and detailed explanations of conversion (along with some links to pattern libraries) are here on All about Needlepoint.
Another method to adapt these patterns begins with a white canvas and uses framed Smyrna Crosses to create both the grid (the frame of Tent Stitches), the pattern (the white Smyrnas) and the fabric showing through the lace (the colored Smyrnas).
It’s also a lovely look as you can see by the samples in her post.
Another great form of adaptation for needlepoint.