This page on the homebrewery

I rather like the concept of a character that can easily resist magic; someone far more vulnerable to martial classes even at very high levels. As such, I've come up with the Way of the Weavemind, using Ki to resist changes to the weave in their immediate vicinity. I imagine this could have been developed by a Githzeri Zerth to cripple Mindflayer Arcanists and Githyanki Gish. It could also fit with a monk order dedicated to fighting liches, beholders, or other evil magic users.

Unlock Arcana
When you choose this archeotype, you gain expertise with the Arcana skill. You may make a Wisdom (Arcana) check to identify a spell after it was cast, rather than an Intelligence (Arcana) check, as you peek into the way the weave was changed to create the spell effect.

You also learn two cantrips of your choice from the bard, cleric, or druid spell lists (they do not need to be from the same list) as well as the guidance cantrip. Wisdom is your spellcasting ability for these cantrips.

You may spend 1 ki point to cast your monk cantrips as a bonus action.

Deflect Magic
Starting at 3rd level, you can use your reaction to deflect or catch magical energy when you are hit by a ranged spell attack or must make a saving throw against a spell that targets you (being caught in the area of effect from a spell dosn't contain enough magical energy for you to use this feature). When you do so, the damage you take from the attack is reduced by 1d10 + your Wisdom modifier + your monk level.

If you reduce the damage to 0, you can catch the energy of the spell if you have at least one hand free and may choose to either unleash or store the energy as part of the same reaction. If you unleash the energy, you may spend 2 ki points to make a ranged spell attack against a creature within 20 feet. On a hit, the target takes damage equal to your martial arts die plus your wisdom modfier of the same type as the spell. If you store the energy, you instead regain 1 ki point.

An ability for flavor and offense, along with a magical knockoff of Deflect Missiles. I'm not 100% sure about the range for attacking with Deflect Magic though (it is currently the short range for Deflect Missiles)

Elemental Fists
You can choose one of the following damage types: acid, cold, fire, lightning, or thunder. For the next ten minutes after you choose this, you deal an additional 1d4 damage of the chosen type in addition to the normal damage of your unarmed strike or monk weapon. You regain this ability at the end of a long rest or after spending 3 ki points to regain it.

I'm wondering if this is a good way of writing a monk ability that refreshes when you spend ki points, but doesn't automatically drain your ki point reserve when used. Given this knockoff of Elemental Weapon is the only consistent damage dealer among the Weavemind's abilities, I'd kind of like to conserve ki points in some situations (such as at tables where the party really only fights once a day).

At 11th level you gain resistance to all spell damage.

Starting at 11th level, you may spend 3 ki point to cast Counterspell or Dispel Magic, using Wisdom as your spellcasting modifier.

You can spend additional ki points to cast either spell at a higher level. Each additional ki point you spend increases the spell's level by 1. The maximum number of ki points (3 plus any additional points) that you can spend on the spell equals half your monk level.

Master of the Weave
From 17th level, you can spend 5 ki points to cast the Antimagic Field spell, requiring no components. Your monk training grants you superior control over the antimagic field, allowing you to cast spells while inside the field, and you can choose to maintain magical effects affecting you for the duration of your antimagic field. Additionally, when you cast the spell you can designate a number of magical items up to your wisdom modifier (minimum of 1) that retain their magical properties within the field. These items do not need to be held or carried by you.

A bunch of defensive abilities, most of them draining your ki point reserve. . The main alternative to spellstopper I've thought of would be allowing them to spend ki points to get a buffed version of mage armor that grants an AC calculation of 13 + Dex + Wis. That would conserve ki points, but grant you a benefit against nonmagical foes. Perhaps as follows:

Molded Armor
Starting at 11th level, you can spend 1 ki point to cast mage Armor. When you cast the spell in this way, the duration is reduced to 1 hour, but you can choose to calculate your AC as 13 + your Dexterity modifier + your Wisdom modifier, instead of the normal effects of the spell.