I don't think so. The Panasonic web site shows the ET5 shipping with polarized 3D glasses whereas these are active shutter. I've never seen a TV that would do both types of 3D. They also don't show up on the accessories list for the ET5 and Panasonic is pretty good about keeping their sit up to date.
No. The TC L55ET5 television uses a passive (non-powered) polarization technology (and comes with several pair). If you want to order (more) 3D glasses for the TC L55ET5, you'll want passive glasses #TY-EP3D10UB, NOT the TY ER3D4MUs.