Queen was never consider a "Metal" band, but their influence on Metal continues to this day. Freddie Mercury's vocal range and style would fit perfectly into a Metal band and Brian May's signature tones are still heard in guitar solos in all genre's of rock.  Their stage presence was also also over-the-top and theatrical, a style Metal would certainly embrace.

Back in 1992 during the "Tribute To Freddy Mercury", James Hetfield of Metallica and Black Sabbath's Tony Iommi joined the remaining member of Queen on stage for a blistering version of "Stone Cold Crazy".

Here's another clip from that tribute Extreme's tribute Melody to Queen, quite impressive.