If they do a fighting event
I've heard a lot of speculation among players, but here and from other places about potential fighting events due to things found in the coding relating to fighting types specifically, and shiny mankey's been found in the files. I remember around half a year ago they did a fighting type event where they released shiny makuhita and meditate.
If they do a fighting event, do you think they might do a new move for evolution during it, like what happened with breloom during the hoenn one? Though even if there is no new move, and extra bunch of fighting types will be great
Though personally I kinda hope they dont have another event so soon after, well, all the other ones they've been doing.
Answers
I agree its likely to get the move. Lucario's position is similar, i do agree, though the difference is metagross is a pseudo legendary, and Lucario evolved from a baby form, i dont think it will get a CD, but maybe a move pool expansion or raid day. Despite its lower bulk, its steel typing could give it a leg up on machamp, though depending on how good aura sphere is, machamp may still edge out (if its only a slight DPS improvement over machamp, it will be in a similar position to breloom depending on match ups, like V things where both take the same level of effectiveness where machamp is better, but agaisnt things where Lucario resists more, like iron tail or SE tyranitar, Lucario will be better)
Meteor mash, it would be good on it, but the attack difference between the two (as well as oddly the bulk difference) is somewhat comparable to the diference between Machamp and Toxicroak. So there will be a noticeable gap in DPS, as well as bulk. I agree Lucario with MM will be great, but metagross will be, much like machamp to toxicroak, just simply better. (Lucario's fighting type might hurt it in fairy match ups)