You can make your own Forge World rules in the new Ad-Mech codex. Here's how.
Warhammer 40K: Adeptus Mechanicus Distant World Rules - Bell of Lost Souls
Adeptus Mechanicus - Page 3 of 16 - Bell of Lost Souls
Warhammer 40K: New Adeptus Mechanicus Detachment Rules - Bell of Lost Souls
Adeptus Mechanicus - Page 3 of 16 - Bell of Lost Souls
40k, Convert or Die
Warhammer 40K: Adeptus Mechanicus Requisition Delay - Bell of Lost Souls
40K: Relics of the Adeptus Mechanicus - Bell of Lost Souls
Start Competing: Adeptus Mechanicus Tactics
What is an area of 40k lore that you wish would have not been fleshed out or altered? - Quora
Adeptus Mechanicus - Bell of Lost Souls
Adeptus Mechanicus - Page 3 of 16 - Bell of Lost Souls
New 40k Adeptus Mechanicus Forge World Rules REVEALED!