[Phantasm]

For a single skill that's valid across several TLs, I use an "I Lived It!" Perk, specifying the lowest TL you learned the skill at. This lets, for example, someone like the Eternal Soldier or a vampire to specify (for example) "Solder/TL8" in a modern-day game while not suffering penalties for using the lower levels of TL. (In Longinus's case, it'd be Soldier/TL2, while in Vlad II Dracula's case it'd be Soldier/TL3 or /TL4.) Think of it as the reverse of the Cutting Edge Training Perk.

Now, using a handful of skills across various TLs I'd consider it a 5- or 10-point Unusual Background; in keeping with the example of Omnilingual, I might go with a 40 point UB for "no penalties to any /TL skill regardless of whether you're in TL0 or TL12+". The character has to have the relevant skills, of course.

This seem valid?