Natural Civ bonuses in scenario

Hey, I am working on transitioning WarCraft 2 maps to AoE2 DE. The idea is that the map and starting location doesn’t change. During this I realized 2 things. The resources were not changing when playing something like Mayans or Chinese and the scouts stayed scouts and not eagles. I’m looking around triggers and other such tings. Inca starts with lamma, chinese start with 6 vils and mayans 4 so that works, just the resources dont change.
Is there any other way to allow the game to start normally with out using a handful of triggers per map? I plan on quite a few maps. Might move on to include some W3 maps.

Edit: After playing around I realized that from time to time when loading a game I had made, the bonuses applied them selves. It was not consistent. Using “Set” instead of “Add/subtract” when handling the res. Id rather not use that in case someone wants to change starting res when playing. Any ideas on how or why that happens?