This is a nice idea. It would bring the game another mini game but i dont like the idea being in PMU. It would make PMU even Less Pmd like then it already is. And if it were to be in PMU the fossils should be as rare as in D/P/PT. Maybe giving the player a shovel to dig in an instance map were theres rocks or just puting the whole D/P underground in PMU. There is one thing i dont like and its the fact that getting a fossil pokemon would be easy. I mean going underground and diging and after like 10 minutes you get a fossil and you revive it…its just not PMD like… It would be better to put the certain Pokemon in a dungeon and having to go trough pokemon that could kill you and having to make faint like 1-10 pokemon to get it.
Example of the fossil-revive thing : ‘’ Hai kabuto! Welcome to the new pokemon world. now your forsed to be with me for your whole life untill i release you ‘’ [laughing?]