Simmer hoisin, chili garlic sauce, honey, vinegar, oil, and salt for the satay in a saucepan over medium-high. Cook marinade 5 minutes, then set it aside to cool.
Prepare pork, cutting it first into thirds lengthwise, then in half crosswise to make 6 pieces. Finally, slice each piece in half lengthwise to make 12 strips, each 4- to 6-inches long. Toss pork strips in the marinade, then thread strips onto skewers.
Rice: Bring water and salt for the rice to a boil in a saucepan over medium-high heat. Stir in rice, cover, reduce heat, and simmer 15 minutes. Remove saucepan from heat. Just before serving, stir in peas and vinegar, fluffing rice until well mixed.
Arrange satay on the grill so the skewers extend over the edge; cover and cook 3–4 minutes. Flip satay, baste with marinade, then grill until cooked through, 3–4 minutes more.
Cucumber Salad: Combine sugar, vinegar, salt, and pepper flakes for the dressing in a bowl; set aside.
To prepare the cucumbers, cut each cucumber in half lengthwise, then scoop out the seeds with a spoon. Discard seeds. Slice cucumber halves into thin slices to make a yield of 2 to 2 1/2 cups.
Toss cucumber and onion slices with dressing until well coated. Chill salad until ready to serve. Salad can be prepared up to 1 hour ahead.