Both of these mice are amazing for usual-sized hands. They are both ambidextrous and have great battery life. But there are still some slight differences between Logitech G Pro Wireless and the G305. So I would compare their disparity in terms of size, weight, RGB lighting, sensor, and battery life.
The size of the G Pro Wireless (12.5x6.35cm) is larger than the G305 (11.6*6.2cm). Based on many seasoned user reviews, G Pro Wireless fits those who have over 19x9cm hands. It supports a larger hand and works better for claw because its rear is sturdy and supports your palm more thoroughly. Otherwise, you should go with G305.
Weight - G Pro Wireless wins
Logitech G Pro Wireless is lighter than the G305 unless you get specific AAA to AA adapter and lightweight lithium AAA batteries for the G305. So Logitech G305 with AAA would become near enough as light as the G Pro Wireless.
RGB lighting - G Pro Wireless wins
Logitech G Pro Wireless is a nice option for an avid fan of RGB lighting. But I would not say it is a perfect option. Its RGB, compared with other brands, is at the bottom tier of RGB markets. The wheel does not seem it lights up while you hand is on it.
Logitech G305, however, has no RGB lighting.
Sensor - G Pro Wireless wins
Logitech allows you to turn DPI up to 16000 with HERO 16K sensor. This means when it moves one inch, the mouse pointer will move 16000 pixels. This sensitive mouse is a pro option for experienced players.
Logitech G305, in contrast, uses Hero 12K sensor and reaches 12000 DPI. Although it has a lower DPI range, it might be good enough for most users.
Logitech G Pro Wireless is a rechargeable mouse with 60 hours of battery life with RGB off.
The G305 has a non-rechargeable AA battery and its battery life is 250 hours.