So I'm a newer DM that's only played in 5e, and I am not good when it comes to translating/converting cool monsters from previous editions into the current edition. Be this the case, I genuinely could use some help/assistance with some problems I am having.

1: I'm trying to find a balanced conversion of the 3.5e Emerald Dragon to Fifth Edition that doesn't nerf it into oblivion, can anybody help?

2: Is there a template for applying shadow dragon features/stats to other dragons? If not does anyone have any wisdom for me? I'm asking because I'm thinking of placing a Shadow Emerald Dragon (An Emerald Dragon who's egg was tainted by shadow) In a twisting cavern (a natural dungeon if you will).

3: Has anyone ran or fought an Obsidian Dragon? How was it?

4: Is there a guide or easy-to-follow template for making a new dragon? I'm just asking since I'm kinda fascinated by the Catastrophe (Cataclysm?) Dragons. I was thinking of making a Pink Dragon (Because Love beam and buuuuubble breath EEEEE), or something else crazy.

Thank you for reading through this!