Your 401k, IRA and HSA all have separate limits that do not interact. $56,000 is the limit for the combined employee + employer 401k contributions for a single plan in 2019, but it sounds like your plan will not allow you to contribute more than $49,000. Still, that's fantastic if you can get there! You can definitely still do your IRA and HSA to the max as well.
The only way for you to put more money into a 401k would be to have access to another 401k, either through another job at an unrelated employer, or in a solo 401k you could establish if you have 1099 employment earnings. The $19,000 employee deferral limit for traditional and Roth contributions is shared across all 401k plans per year, but employer contributions and employee after-tax contributions are not. Good luck!