// typings/express.d.ts

  declare module Express {
    export interface Request{
      [key: string]: any
    }
  }


  // example.ts

  import express, { Request, Response, NextFunction } from 'express'
  interface RequestWithModels extends Request {
    model : MyModel;
  }

  router.get('/path',
    getHistory, //<- тут ошибка
    returnHistory
  )

  async function getHistory (req: RequestWithModels, res: Response, next: NextFunction) {
    // smthing
  }

type Foo = { [key in string]: Bar };

interface Foo {
  [key: string]: Bar
}

Record<string, Foo>