This is a very interesting piece of glass for sure!! In some ways it reminds me of Kralik overshot pieces. In some ways it reminds me of Welz examples, but I have not really seen much overshot by them at this point. Lastly, the style of frit on the surface of this does not remind me of either company. Generally they have what I would refer to as kind of "sugar frit:, which simply means that it is kind of granular in nature.
That said, the frit on this reminds me more of larger irregular applications that have been re-fired to kind of smooth the surface a little more. It is similar in style, although a little more dense than an overshot piece I own in pink, which is in an Art Nouveau mount. That piece was initially attributed to Kralik by Alfredo, but I later changed the attribution to Rindskopf when I saw the same mount with a Rindskopf Papillon example in the same mount. Still not sure that is 100% correct though.... but I think not Kralik for sure. This style of frit is far less common.
The ribbing on this is reminiscent of the ribbing on some of the trophy pieces by Welz, although at this point without additional evidence I would be hesitant to state Welz for this piece....
I am very interested in seeing a shot of the mouth of the vase, which generally allows the true color combination of the ground to show through.... It is that way with the Kralik overshot and also glue chip decors.
Craig