Is it deer resistant?

Yes

Japanese Medlar is deer resistant.

Eriobotrya japonica

Deer: Rarely
Height: 25 ft (7.6 m)
Spread: 25 ft (7.6 m)
Zones: 8–12
Light: Full sun

Perennial
Shrub
Tree

Japanese Medlar (Eriobotrya japonica)

Photo: Minja Klarić · CC BY-SA 4.0

Also called Japanese Plum, Loquat

Perennial Eriobotrya

More details

Light: Full sun, Partial shade
Water: Medium
Type: Perennial, Shrub, Tree
Maintenance: Low
Growth: Fast
Bloom: Fall, Winter
Foliage: Evergreen
Features: Drought tolerant, Edible, Flowering, Poisonous
Best uses: Accent, Coastal, Flowering tree, Houseplant, Lawn, Patio, Play area, Privacy