This is the BSV library that sensible-contract/web3.js mainly depends on
npm install @sensible-contract/bsv
const bsv = require("@sensible-contract/bsv");
const {BN} = require("@sensible-contract/bsv");
import * as bsv from "@sensible-contract/bsv";
import { BN } from "@sensible-contract/bsv";