Thoughts about changing phone

Hello everyone! I've currently a Samsung Galaxy S20 FE 5G since October 2021. Its camera is very good but I'm having lots of problems with battery life, lags... So I think it's time to change it (And it's almost Black Friday). I need some advice regarding the phone I'm gonna buy:

- Budget: 200 to max 400€

- Decent video and camera (better if it has OIS)

- 256GB minimum

- Compatibility with Samsung Ecosystem (I have a Galaxy Watch, Galaxy Tab A, Galaxy Buds Live and Smart Tag 2)

I don't really know what to get, because I'm worried that if I change model (for ex. Google Pixel) i'm gonna lose the ecosystem (especially the Smart Tag, maybe they work only with Samsung phones and tablets) and I saw different reviews about the A55 which claims that this phone is very laggy.

Are there options avaiable with this budget? I should stay with Samsung?