Hi,
do not try this 😉
If you want, you need to check booth sides. If you'll use an mobile device at the other end, the antenna is very bad. Best way is to use a high gain directional antenna. The signal gain from the antenna is added to booth ways, sending and receiving. This is why you should use more antenna gain instead of higher TX power.
You can check what antennas are available. Try it with 10dBi antenna gain. But it depends from site to site. Is it a big open area without reflection, is it a area with reflection? Have the client a line of sight? Without testing it's not possible to give a recommandation.