All credit goes to DemonGodMitchAubin on VS Battles Wiki: https://vsbattles.fandom.com/wiki/User_blog:DemonGodMitchAubin/FE3H_Dodging_Calcs

The Original Calc[]

Distance Moved[]

In Fire Emblem Three Houses, the characters are able to dodge both Meteors and the Immaculate One's Hoarfrost (Hoarfrost is a lightspeed attack) right as it is above their head, so I will find out what that results in. Everyone dodges the same distance whenever they dodge an attack, so I will use Dimitri's dodge animation to get an average distance moved. I'll also do a re-calc of dodging bolting just so we can have a Three Houses version.

Dimitri's Height = 1.88 Meters = 949 px

1.88 Meters/949 px = 0.00198 Meters per px

Distance Moved = 594.12 px = 1.18 Meters

The characters don't begin to dodge until the spell is right above the head of the person, so I'll lowball to 1 Foot, which is 0.3048 Meters

Calculation = ((Distance the character moved in Meters)*(Speed of Attack))/(Distance attack was from person)

Dodging Meteor[]

Speed of Ablation = 2000 m/s

((1.18 Meters)*(2000 m/s))/(0.3048 Meters) = 7742.8 m/s or Mach 22.75 (Hypersonic+)

Dodging Bolting[]

Speed of Lighting = 440000 m/s

((1.18 Meters)*(440000 m/s))/(0.0254 Meters) = 20440944.9 m/s or Mach 5005.77 (Massively Hypersonic+)

Dodging Immaculate One's Hoarfrost[]

Speed of Light = 300000000 m/s

((1.18 Meters)*(300000000 m/s))/(0.3048 Meters) = 1161417322.8 m/s or 3.9 c (FTL)

Hypersonic+ scales to Fodder tier, FTL scales to God tiers. This scales to both movement speed as well as combat speed.

Recalculation[]

I recalced the above calculation, but lowballed it to an inch (0.0254 meters) since the OP says that the dodging animation starts right when the spell projectile is right above them.

Dodging Meteor Recalc[]

Speed of Ablation = 2000 m/s

((1.18 Meters)*(2000 m/s))/(0.0254 Meters) = 92913.6 m/s or Mach 273 (Massively Hypersonic)

Dodging Bolting Recalc[]

Speed of Lightning = 440000 m/s

((1.18 Meters)*(440000 m/s))/(0.0254 Meters) = 20440944.9 m/s or Mach 59594/0.06c (Sub-Relativistic+)

Dodging Hoarfrost Recalc[]