Hi,

I had the same issue and found a post with a working solution. I've included the code I'm using below in case you haven't written anything yourself.

const myDateRangeSelect = document.getElementById('date-range')
    myDateRangeSelect.addEventListener('valueChange.mdb.select', (e) => {
        checkDateOption(e.target.value);
    })

    const datepickerWithFilterStarting = document.querySelector('.datepicker-startDate');
    const datepickerWithFilterEnding = document.querySelector('.datepicker-endDate');

    const datepickerWithFilterStartingInput = datepickerWithFilterStarting.querySelector('input');
    const datepickerWithFilterEndingInput = datepickerWithFilterEnding.querySelector('input');
    const filterFunctionForStartingDate = (date) => {

        const isBeforeEnd = date < Date.parse(datepickerWithFilterEndingInput.value || new Date());
        const isAfterBeginning = date > new Date(2017, 0, 0);

        return isBeforeEnd && isAfterBeginning;
    }

    const filterFunctionForEndingDate = (date) => {
        const isBeforeEnd = date < new Date();
        const isAfterStart = date > Date.parse(datepickerWithFilterStartingInput.value || new Date(2017, 0, 0));

        return isBeforeEnd && isAfterStart;
    }

    let starting = new mdb.Datepicker(datepickerWithFilterStarting, {
        min: new Date(2017, 0, 1),
        filter: filterFunctionForStartingDate});
    let ending = new mdb.Datepicker(datepickerWithFilterEnding, {
        max: new Date(),
        filter: filterFunctionForEndingDate});

    datepickerWithFilterStarting.addEventListener('dateChange.mdb.datepicker', (e) => {
        ending.dispose();
        ending = new mdb.Datepicker(datepickerWithFilterEnding, {filter: filterFunctionForEndingDate});
    })

    datepickerWithFilterEnding.addEventListener('dateChange.mdb.datepicker', (e) => {
        starting.dispose();
        starting = new mdb.Datepicker(datepickerWithFilterStarting, {filter: filterFunctionForStartingDate});
    })