Is E-TTL Universal?

No, it's the opposite of universal. It is proprietary and specific to Canon. Each brand has their own specific flash/camera communication system. The only thing that's universal is the sync (fire) signal [which is a short between ground (rails) and the center contact of the hotshoe], because that's part of the ISO standards for flash hotshoes.

Are high-end, high-power studio strobes integrated into the E-TTL flash exposure system?

Most are not. There are a few rare/newer exceptions (e.g., Profoto B1, and, at the lower-end of the scale, the Godox AD600 and Phottix Indra) that have been reverse-engineered, like 3rd party speedlights, to work within Canon's eTTL/HSS protocol [at least as it stands at the moment]. And these may eventually become more prevalent. But they aren't particularly common at this time. They are system-specific; there are different models for, say, Canon's system and Nikon's system, and compatibility may not be identical to OEM TTL-capable gear.

In addition, being able to use the TTL/HSS capabilities of the rare strobes that can do it may rely entirely on using a specific same-brand triggering system (e.g., Profoto Air, Godox X1, and Phottix Odin, respectively) with a camera in the same system that can perform these functions (i.e., a camera body with TTL/HSS capabilities on the hotshoe). For example, a Nikon D3300, which cannot perform HSS, still cannot do HSS with one of these strobe/trigger combinations: the whole chain has to be capable of these features.

Do they have the manual settings option?

The vast majority of studio strobe only have manual power setting options, and do not perform HSS, although, depending on the triggering system, may have tail-sync capability.