Skyrim SE: Alternus - The Black Knight (My Personal Build)

This is the build that I used in my first structured play-through of the game and first build I created. It is what I use every time I start a game on a new version. It is incredibly powerful; powerful enough to use on Legendary difficulty without much trouble.

Race: Go for Breton. Their racial abilities become useless in the late game for this build, but it is invaluable in the early game for Legendary difficulty. They have a 25% resistance to magic and can use their racial ability to gain 50% magicka absorption for 1 minute. We will be achieving 100% magicka absorption later on, so this will be useless.

Standing Stone: I took the Lord Stone straight out of the gate for the extra magicka resistance and armor. I skipped the warrior stone because you level combat abilities really quickly on Legendary due to how many times you have to hit the enemy, and leveling too quickly is kind of a detriment on legendary since enemies scale to your level. The longer you can avoid going up against Draugr Death Lords the better. Later, you should grab the Atronach Stone. If you combine that with the Atronach perk in the Alteration tree and then add Vampire/Necromage combo to it, you will have 100% magicka absorption and spells will no longer affect you.

Stat Distribution: Ignore Magicka, it's useless here. Instead put all of your points into Health and Stamina at a 4:1 ratio, respectively. At lvl 50 you should have 200 Stamina and 490 health.

Skills:

Weapon: As soon as you hit lvl 20, do the Daedric quest to get the Ebony Blade. This weapon may not be the best when it comes to physical damage, but it hits very fast and absorbs 30 health for every hit. As long as you are hitting the enemy, you can't die.

Armor: In the early game, I rad to Solitude and got the Imperial Champion armor from the Creation Club. It is very good armor, but it has it's own enchantments on it already. Once you can get some Daedric armor and have high enchanting, enchant your own gear and ditch the Imperial Champion Armor.

Enchantments: Enchant any piece of armor you can with Fortify Two-Handed. This will make the Ebony Blade's Physical damage more usable. Also get Stamina Regeneration on your armor to mitigate the negative effects of being a vampire in the day time. The health regen problem will be taken care of by the sword and the magicka regen problem won't matter.

Skyrim SE: Paladin of Stendarr (Creation Club Build)

Warning: this build utilizes items only obtainable via the exchange of real life currency in the Creation Club. I am aware of the general distaste of the Creation Club and its products, I just don't care. If you care that much about it, I am sure there are some free mods that can do something similar.

Race: I chose the Breton for their tank abilities. They have a natural 25% resist to all magic and an active ability that grants 50% spell absorption. Since this build does not use the necromage/vampire ability to reach 100% spell absorption, their passive will be much more useful than in other builds I have used. If combined with the Atronach Stone, their active ability will stack and you can achieve 100% spell absorption for 60 seconds that way.

Standing Stone: This character utilizes both magic and combat abilities, so grab the lover stone ASAP after you leave Helgen. This will increase the rate at which you gain EXP for all skills by 15%. Later - and I know this is an obvious choice - grab the Atronach Stone for 50% magicka absorption.

Stats: Distribute your stats at a 2:2:1 ratio in Health/Stamina/Magicka. Stamina will be imperative because Stendarr's Hammer uses stamina of every swing (plus it weighs a whopping 100 units). Magicka is less important though quite useful. We will need it to heal and use Stendarr's Aura, but not for anything else, so 1 level every 5 levels will be more than enough. Health is also quite important because Stendarr's Hammer swings quite slowly, so you will likely be taking quite a few hits. By level 50 you should have 200 Magicka, 300 Health, & 300 Stamina without any additions from enchantments.

Skills:

Spells: This build utilizes restoration exclusively for it's magic. In the early game, use the basic Healing spell, but ultimately go for Close Wounds for your personal heals. Vampires Bane and Stendarr's Aura from the Dawnguard DLC will be your main offensive spells.

Weapon: Your main weapon is going to be Stendarr's Hammer. It is a power 2-handed weapon you can buy from the Creation Club. Be warned, it costs stamina every swing much like combat in Oblivion. It also weighs 100 units, so you won't be looting much.

Armor: Wear the Heavy Armor variant of the Crusader Armor from the Creation Club. It has it's own enchantments which is why there are very little enchantment perks chosen. There is also a light armor shield that you can wear on your back and it will add just a little extra armor rating, hence the perks taken from the Light Armor tree.