No, the Missingno glitch has been removed. Since a lot of data has been shifted around, it wouldn't even do what people wanted it to do anymore anyway. Also, while the Mew glitch technically hasn't been fixed, doing the Mew Glitch will give you a Spearow instead of a Mew, again due to things being different internally. In terms of Mew, you can encounter one legitimately now through a new event. I may eventually add a "safe" missingno as an easter egg, but the glitch for him has been removed completely. I'm sorry :/
