Frigates yes, cruisers and capital ships no.
The frigates really do come off as terribly non-descript, although a few tech upgrades change them up a hell of a lot. The phase missiles, when working well instead of negating their own benefit, will be the ultimate dunov counter, their meatgrinder ships upgrade into self repairing freaks that take a lot more of a beating than cobalts to start with, and then get to repair the damage without any help. The planet bombers are still planet bombers, if better ones, and the flak frigates are just flak frigates, but the two sides are not identical even just in frigates, nowhere near as close together in function as supreme commanders units are.
With the cruisers, only the carrier is a matchup for TEC cruisers. TEC have real support cruisers, they actively support the other ships, repairing and restoring shields, increasing firing range. The kodiak on the other hand is a purely offensive meatgrinder, with a tech upgrade to make it a powerful persuit vessel too. The Vasari by comparison have little in the way of support abilities, an instant hull boost with accompanying armor, phase jump inhibiting capabilities, and very nice disabling shots. Their kodiak variant is likewise different. Instead of being a persuit type, it's yet again a disabling type. It slows the enemy, letting your entire fleet persue and destroy it instead. None of the capital ships behave the same way, the TEC capital ships are designed to support each other, range increases, shield restoration, the ultimate bomber defenses. Their carrier is a standoff weapon, sitting at the edge of gravity wells daring you to come and screw with them and their missile platforms while they bomb you and steal your income. The battleship is the perfect target, massive shield mitigation in combination with dunov shield restores gives you an invincible target to run into packs of frigates, defense platforms, anything and everything. The dreadnaught is a pack killer, dot's and multiple ship targetting abilities, with the extra cheesy level 6 missile spam radius effect ship killer. The battlecruisers are support ships, shield restore, extra range, minor disabling abilities, and cease fire.
The Vasari have no restoration, their dreadnaught plays the same role early on in being able to hit multiple targets with abilities, but it's primary role is in planetary destruction, while the marza's is secondary and minor. The battleship isn't so much a meatshield as it is a ridiculously punishing damage dealer, huge weapon cooldown bonuses accompany a very nice shield regeneration boost. It can tear through anything very rapidly at high levels, including a Kol. The carrier, instead of a standoff weapon, is the only mobile repair station they have, and a mass effect one too. It's a front line support ship, regenerating hulls and phasing strike craft in and out to kill the enemy faster. The two others are likewise completely different, the marauder doesn't even have a near facsimile, a fast strike capital ship doesn't exist on the TEC side, let alone one that speeds up the entire fleet and lets them jump further out. At level 6, the portable phase gate is more than just different, it's a side defining tactical strike capability that the TEC can't even prevent, let alone duplicate. The Vasari colonizer is almost as different, the most powerful damage ability in the game, an area effect jump blocker and that wonderful vacuum cleaner of a level 6 ability that sucks up half a maxed out terran planet.
TEC are about group strength, complimenting abilities combined to create an invincible fleet that stops for no one. The Vasari are about wiping the floor with anything smaller and leaving no survivors, or blowing past the defenses in a surprise attack, leveling the planet in seconds, and jumping straight home if they run into that invincible fleet before they're finished with their conquest.
