Yes, you can use Elux e-liquid in any refillable device, but it's best suited for lower-powered MTL (mouth-to-lung) devices, like regular pod kits and starter kits.
Since Elux Legends e-liquids use nicotine salts, they're not ideal for high-powered sub-ohm devices, as these devices produce large clouds of vapour and the liquids have a high nicotine concentration, which could be overwhelming for most users. Sub-ohm devices work better with high VG e-liquids, like those found in short fill bottles. While Elux e-liquids will still work in sub-ohm setups, you might find the experience too harsh, with potential leakage and an overpowering nicotine hit.
If you are unsure what type of vaping device you have, most devices are lower powered MTL vapes, so chances are you will be fine using Elux liquids. High powered sub-ohm devices are generally larger devices that produce large and intense clouds of vapour.