Prep the Corn: Pull husk back from each corn cob and remove the silk. Recover corn with the husk.
Soak Corn: Dissolve salt in a large bowl of cold water. Add corn and immerse. Soak corn for 10 minutes. Remove and drain well. Use a paper towel to pat dry.
Preheat the grill to medium-high heat. Brush the grates with olive oil or spray with grilling spray.
Pull back the husk and arrange the corn directly on the grill grates. Grill for about 12 to 15 minutes, turning occasionally, until the corn is tender and slightly charred in spots
Prepare the Topping: While the corn is grilling, stir the softened butter, lime juice, lime zest, and chili powder in a small bowl.
Mayo-Crema: In a separate small bowl, stir together the mayonnaise with the Mexican crema. You can use more or less crema to thin to your taste.
Seasoned Butter: Once the corn is done, immediately brush it all over with the chili lime butter mixture. Let stand for a few seconds to melt, then drizzle or slather with the mayonnaise crema mixture. (For chili lime corn, skip the mayonnaise and crema.)
Sprinkle the corn with cotija cheese and chopped cilantro over the top.
Season with salt and black pepper to taste then serve hot with extra lime wedges on the side.