Seen this concept here and there in comments but not anyone else who has actually tried it out so here's my sharing on my Inquisitor which, through Brass Dome, Leadership's Price and passives, hit 90% ele res to dual wield Nebulis, without PoL/PoI nor a shield, getting 1200% inc cold damage with CotB conversion.

Disclaimer: Expensive and probably not that great for the cost, but it works. Still needs more optimising.

Build Concept:

My latest attempt to min-max something off a particular concept got a huge boost when Gwen granted me a Mageblood and I was able to try out a concept that caught my eye in the patch notes. With the new Brass Dome (up to 5% max ele res) and more passives granting max res on the tree, it is now viable to hit unbuffed 90% max ele res as a solo player. Namely, without cluster/timeless jewels, you could use corrupted Brass Dome (5+1%), max roll Leadership's Price (3%), Prismatic Skin cluster (3%), Soul of Steel (1%), Anointed Flesh (1%) and anointed Crystal Skin (1%) for a total of 15% to all max ele res.

Anyone who has been part of the Herald/Aurastacker era knows the power of Nebulis with cold conversion, and with no shield requirements I was able to wield 2 as a solo build (almost all dual Nebulis builds on poe.ninja are meant for group play with an aurabot). This makes no further investment in increased damage needed.

Leadership's Price introduces new restrictions and opportunities. While balancing stats is a pain, alt ailment conflux means getting max crit is trivial if you are able to get high Brittle stacks. So going crit was a natural progression, and crit multi became an effective but expensive secondary damage scaling.

For defences, 90% max res and high armour from Brass Dome makes armour investment pretty natural. Nonetheless, the lack of flat life on gear (due to dome and all the uniques) means that getting a high life pool is challenging. There are other options, but I chose to go Inquisitor with Corrupted Soul to have more eHP. Inquisitor also comes with really good recovery and the playstyle ends up really similar to a Guardian Aurastacker, with fantastic effective hit pool and good recovery (around 2k Life and 1k ES regen, not including Divine Shield). The recovery also make going perma RF and LL for pain attunement feel safe for a good DPS boost.

Finally, the elephant in the room: Do you need Mageblood? No you don't, but gearing to get enough res might be a bit of a pain and you will probably have trouble getting much chaos res. Also, Mageblood provides so much armour and movespeed.

Assessment:

Pros: Build, as expected, is very tanky, with max res, high armour, recovery, crit immunity, major ailment immunity etc. No March of the Legion or friends needed.

Cons: Frankly, the DPS is mediocre for the level of investment, though I'm sure I'm not building this optimally. Arc feels nice for normal mapping but most likely the correct thing to do is to respec for brands instead. Alternatively, you could probably drop Determination and go Hatred/Wrath but I do enjoy the very forgiving tanky playstyle now.

Can you play this on a budget? Technically it's doable with just normal Brass Dome and a non-max-roll Leadership's Price if you use the cluster jewels (Prismatic Carapace) or get max res nodes on your Glorious vanity. But probably not advised.

Anyway, happy to hear suggestions on improvements!

POB: https://pastebin.com/5qVUQ9ut

Char: https://www.pathofexile.com/account/view-profile/EternalSceptic/characters?characterName=YetAnotherGimmick

Gameplay:

Hydra with Mino: https://streamable.com/bivppo

Sirus 9 (earlier on without DD Nebulis): https://streamable.com/cun961

The Hidden (forgot to on RF): https://streamable.com/2xozt7

Wave 30 Sim complete (Can facetank both bosses but DPS is too low to farm as failing to hit max brittle - Kosis fight really too long): https://imgur.com/a/ms5cTzS