Executors are expected to resolve any disagreement between themselves although in an extreme situation one can apply to the court for another to be removed from the executorship. This isn’t such a situation though.
I don’t know if the three executors are the sole beneficiaries of the estate. If there are other beneficiaries the executors have a duty to them to obtain the best price reasonably obtainable for the house and to distribute the proceeds as soon as reasonably possible. The other executors’ unwillingness to reduce the price leads me to suspect that they (maybe you too) are beneficiaries.
You say the house has been on the market since last year at too high a price and that the other two executors refuse to lower the price, but want to move to another estate agent who says it is overpriced. Do they insist that the other agent markets it at the same excessive price if he is willing to do so, or will they accept his professional advice, as they should as they must act in the best interests of all the beneficiaries? Holding out for an unattainable price is not acting in the best interests of the beneficiaries, which puts them in breach of their duties.
Will they take the advice of the new agent and agree to instruct him, dispensing with the services of the existing agent? It looks much better if a property comes to the market with a new agent rather than being reduced - the house is doubtless advertised on Rightmove and one can see at a glance whether a property was put on the market and when the price was reduced. Much better to start afresh at a sensible price.
I assume the property is empty - if so, I hope the insurers have been told of that otherwise if it or any contents are damaged they will refuse a claim. Also, whilst the house is unsold outgoings are having to be paid - the executors shouldn’t lose sight of how they mount up.
I hope I have helped and that you feel less alone.