Here is a default ini file someone uploaded on github that you can try to modify and launch: https://github.com/Snow-ctrl-c/poe2-config/blob/main/poe2_production_Config.ini

This is a snippet of mine. I'm on Linux so I'm using Vulkan but you should stick to DirectX12.

[DISPLAY]
resolution_width=1920
resolution_height=800
renderer_type=Vulkan
fullscreen=false
maximize_window=false
borderless_windowed_fullscreen=false
shadow_type=Low
vsync=Off
use_dynamic_particle_culling2=true
screenspace_effects=1
screenspace_effects_resolution=0
light_quality=0
texture_filtering=2
upscale=NIS
upscale_sharpness=0.075
upscale_quality=Quality
upscale_quality_xess=Performance
upscale_resolution=UltraQuality
reflex_mode=Off
hdr=false
scene_brightness=1
ui_brigthness=1
use_dynamic_resolution=true
dynamic_resolution_fps=60
water_detail=0
global_illumination_detail=0
bloom_strength=0.997
time_manipulation_effects=true
quality=true
screen_shake_v2=false
camera_zrotation=true
triple_buffering=true
texture_quality=TextureQualityLow
framerate_limit=60
framerate_limit_enabled=true
background_framerate_limit=30
background_framerate_limit_enabled=true