The ESP32-S3-WROOM1 module is FCC certified for its own Wifi and Bluetooth emissions when used by itself.

And, well -- that's certainly good.

But the FCC rules cover more than just Wifi and BT, and the whole rest of the widget also needs to comply with them. Of particular interest is FCC Part 15 Subpart B, which covers unintentional radiators. The device would need to comply with Part 15 Subpart B even if it had nothing to do with Wifi or BT.

Putting one part that is certified for one issue into a device doesn't extend a magical blanket of compliance to everything else that the whole of the widget contains.

Does the SPI or I2C bus (or anything else) leak RF beyond allowable limits? Eh, who knows. I certainly don't know. It's easy to say words like "it should be fine," but without testing then nobody actually knows.

The CE mark, meanwhile: That mark means exactly nothing in the US, where the author is located and the devices are sold from. The United States has zero regulatory recognition of any of the processes and/or tests that CE may cover. People often confuse this issue, wherein: They don't think it be like it is, but it do.

A fun fact of the CE mark, is that it's also used to signal "Chinese Export" deceptively, with the marks being almost identical beyond spacing.