One other issue is some Panasonic lenses seem to have a tendency for purple fringing on some OM/Olympus bodies. The conventional wisdom is this is due to the Panasonic lenses and the OM/Olympus sensors having different cutoff levels for IR light, and that IR light is causing the purple fringing. The lens that is most complained about is the Panasonic 7-14mm f/4, particularly with the older bodies like the E-m5 mark I. I've seen reports that newer OM/Olympus bodies have more IR blocking, but I think I've seen reports that it still exists with newer bodies.
And there I was, thinking all along that it's an issue at the UV end of the spectrum - an understanding in which I'm seemingly not alone...
https://alanwatsonforster.org/writing/mft-purple.html
Yep. I didn't post it since I don't recall anything more recent (it was done in 2017). I would have hoped the newer sensors and designs would have fixed this. I see another post in this thread that says there are still problems with the OM-1.
I was curious, and I went to B&H. There isn't much selection that is equivalent to the Wratten 2E that blocks UV light at 390nm. For round filters, your choice seems to be "Formatt Hitech" and "Nisi Armour", in the $50-60 range. I was amused the the "Nisi Armour" filter is explicitly rated to be explosion proof.
Tiffen makes a 77mm filter for $92, but I don't see other sizes.
When I search for 2E filters, I also see Leica branded filters, but the detail doesn't explicitly says it blocks IR at 390nm. And of course these filters are at Leica prices ($150-450). At that price range, the cost of adding the filter means it likely is just cheaper to go with OM/Olympus branded lenses.
And the Panasonic 7-14mm doesn't take filters. I've seen adapters that take 105mm circular filters, but I didn't notice any 2E filters that are that large. You can buy a Kodak 4x4" Wratten 2E filter for $99 and fashion your own filter holder.