Dynamically switching modes -- pair of 3-way switches controlling pair of lights vs. individual control of each light from nearest switch

I want to add a Shelly device to an existing lighting circuit to toggle the function of the circuit.

Currently, I have a 'standard'¹ 3-way lighting circuit with two switches at opposite ends of a space, controlling a pair of lights in the space -- one light is near each switch. I seek to be able to switch between this mode of operation (i.e. where both lights are controlled, together, by either switch), and the mode of operation where each light is independently controlled by only the switch nearest it.

To be clear, I do not want to change this permanently to two separate simple light-with-single-pole-switch circuits. Rather, I want to add a Shelly device to the circuit to make that mode be one of two selectable modes of operation (with the other mode being just as it is now. The many offerings of devices is somewhat confusing, as is the specs talking about 50VDC. This is a 120VAC (60Hz) lighting circuit.

Questions: What device(s) should I use? Will it have easily-configurable logic to control each light in the two different ways (ether changing the state of both lights whenever either of two switches changes state, or by ignoring one switch and 'passing-through' the state of the other switch to the light)? Lastly, can this be done with just a single Shelly device to control both lights independently, or do I need two separate Shelly devices?

¹When I say 'standard' 3-way lighting circuit, I mean there are two 'carrier' wires between the two light switches, with one or the other being hot at any given time, depending on the state of the first switch, Then the state of the second switch determines which of those two 'carrier' wires is connected to the load.

So, I tried a Shelly 2.5, since it had two switches and two inputs. I simply hooked it up to my network to see what settings were available in the UI. I've not yet wired it into the circuit.

I at least learned some of the lexicon so I'll know what words to use now. More important than Shelly-related nomenclature, I learned that I'm using the wrong terminology for my audience. In the U.S.A, from whence I hail, we call a single-pole, double-throw (SPDT) switch a '3-way' switch, while in the EU, it is called a '2-way' switch. I'm talking about a circuit wherein you can control a light (or lights) from either of two switches (e.g., at the top, and at the bottom, of a staircase). Desciption linked.

I found a mode of the Shelly 2.5 that treats the two 'channels' (i.e. lamps) independently (i.e. wall-switch one ('ws1') controls lamp1, while wall-switch two ('ws2') controls lamp2, with no interaction between the two channels -- that's one of the two desired modes.

The other desired mode seems like it would be a common desire -- to make a '2-way' (UK) / '3-way' (US) circuit for a pair of lights, using two regular toggle switches. Interestingly, I did find a mode ('Cycle Switch') in the Shelly 2.5 that cycles through these 4 states:

That tells me that there is NOT a hard-line separation of the two channels, so it seems possible to do what I want -- have each switch act as an 'edge switch', that toggles the state of the pair of outputs together. Is that an option in there somewhere and I'm just failing to recognize it? I can't imagine that not being one of the options, given the really exotic one shown above.

Two other points of ambiguity regarding the 'Cycle Switch' mode described above, (which I could actually fall back to if it works with regular toggle switches): While it is clear that mode would work with momentary switches (i.e. pushbuttons), it is not at all clear if it would work with regular toggle switches (i.e. with toggle switches acting as 'edge' switches to cycle to the next state upon each change. It is also not clear if that mode is intended to accept inputs from either of the two wall-switches, or if one of them would be disabled, or what. The UI allows you to configure the two 'sides' of the Shelly 2.5 independently, so you could configure one side with this mode and the other side with a straight toggle switch control mode -- which one would prevail?

After hours of research and many rabbit holes, I finally figured it out. It was so hard because of the lack of clarity regarding the various lines of Shelly products. The key was this: The "Plus" and "Pro" series have enabled mJS scripting. mJS scripting will seemingly allow me to configure the mode of operation however I want. The Shelly 2.5 (which I tried first) does not allow mJS scripting, and is thus limited to the pre-configured modes.

Answer: It looks like a Shelly Plus 2PM, with the addition of a custom mJS script, will allow me to do what I want.

Thanks for the responses and consideration, all!