Swiftwing rambles plus some BlitzOpWing
Swiftwing fucking loves to be squished, any continuity the more weight the better, crush him into a metal frisbee, it's especially good when whoever squishing him is idling and running their engines because oh fuck yeah VIBRATION good shit like a deep massage, because I headcanon Insecticon to basically have comfort/healing frequencies like a cat purring to feel better when one of them is injuried, unwell, generally emotionally not great their solution is usually to squish the fucker get laid on top of and rumbled, so it's incredibly soothing for Swiftwing when he's squished reminds him of home and comfort. Biologically the rumbling probably softly vibrates the body enough that nanite fuel lines don't get clogged up with repair nanites and gently stimulates joints and struts and structures ect enough that they don't lock up and become painful from being locked or are overworked that balance of keeping the muscles warm so to speak without stressing, and subconsciously it's probably similar to being a sparkling being held by a larger vibrating frame because they're always in motion and even those factory built the factory line probably would've been rattling, it's comforting safety so it helps the physical and the mental puts that catbug in your lap and let's them purr, insecticons just have a higher range of frequencies that they specialise in it more
This also means if Optimus is like arg,, my helm hurts because he's got a stress migraine or he stared at a light too long working or from an old injury or something Swift is just I know what will fix this. And lies on his face, or probably more accurately cuddles and curls around Optimus head and he's just a bit, ah yeah, temperature, exactly what I need /negative sarcastic, and then he starts to rumble and vibrate and he's like hm yeah that's gonna help my tension lines. He doesn't mean to be mean, his headache makes him a bitch he's allowed. And then 2 minutes later he's like ¿¿¿¿¿what the frag why is this working???? So perplexed he's thinking with Spanish punctuation
Catch him laying on Blitzwing back rumbling soothing his spinal struts and wings, cause let's be real he's big even if he's built to be fully functional he probably still gets aches it's a symptom of being alive things hurt, he's not built to a disadvantage but he's got a big chest and backpack and carrying the weight of my love for him and being one of the most fun iterations of Blitzwing, it's a lot of weight to carry his back hurts
Had Swiftwing been with them at a point in time where he was comfortable and confident in his relationship with them he would've been all over them when carrying, that things your very own portable heated vibration pack that comes with hands to massage and words of affirmation fuck yeah. He doesn't need to, but he totally would softly knead on Optimus thigh or gently over the plating of his abdomen no claws digging in just little petting motions because touch the love<3 and obviously Blitzwing gets the same treatment, he could sit on the sofa and lean back on Swift crushing him into the back pillows and he'd just start purring, Optimus like you good? And he sees the sofa cushion wiggling as a hand pops out to 👍 at him, he's so happy don't remove him
He's so god damn tactile and it's so funny that half the BlitzOpWing ships he is actively running away from touching, you want to touch so bad and be all over them you're only making yourself miserable go grab his hips.